Line data Source code
1 : // Copyright 2013 The LevelDB-Go and Pebble Authors. All rights reserved. Use
2 : // of this source code is governed by a BSD-style license that can be found in
3 : // the LICENSE file.
4 :
5 : package pebble
6 :
7 : import (
8 : "bytes"
9 : "context"
10 : "fmt"
11 : "iter"
12 : "math"
13 : "runtime/pprof"
14 : "slices"
15 : "sort"
16 : "sync/atomic"
17 : "time"
18 : "unsafe"
19 :
20 : "github.com/cockroachdb/crlib/crtime"
21 : "github.com/cockroachdb/errors"
22 : "github.com/cockroachdb/pebble/internal/base"
23 : "github.com/cockroachdb/pebble/internal/compact"
24 : "github.com/cockroachdb/pebble/internal/keyspan"
25 : "github.com/cockroachdb/pebble/internal/keyspan/keyspanimpl"
26 : "github.com/cockroachdb/pebble/internal/manifest"
27 : "github.com/cockroachdb/pebble/internal/problemspans"
28 : "github.com/cockroachdb/pebble/internal/sstableinternal"
29 : "github.com/cockroachdb/pebble/objstorage"
30 : "github.com/cockroachdb/pebble/objstorage/objstorageprovider/objiotracing"
31 : "github.com/cockroachdb/pebble/objstorage/remote"
32 : "github.com/cockroachdb/pebble/sstable"
33 : "github.com/cockroachdb/pebble/sstable/blob"
34 : "github.com/cockroachdb/pebble/sstable/block"
35 : "github.com/cockroachdb/pebble/vfs"
36 : "github.com/cockroachdb/redact"
37 : )
38 :
39 : var errEmptyTable = errors.New("pebble: empty table")
40 :
41 : // ErrCancelledCompaction is returned if a compaction is cancelled by a
42 : // concurrent excise or ingest-split operation.
43 : var ErrCancelledCompaction = errors.New("pebble: compaction cancelled by a concurrent operation, will retry compaction")
44 :
45 : var flushLabels = pprof.Labels("pebble", "flush", "output-level", "L0")
46 : var gcLabels = pprof.Labels("pebble", "gc")
47 :
48 : // expandedCompactionByteSizeLimit is the maximum number of bytes in all
49 : // compacted files. We avoid expanding the lower level file set of a compaction
50 : // if it would make the total compaction cover more than this many bytes.
51 : func expandedCompactionByteSizeLimit(
52 : opts *Options, targetFileSize int64, availBytes uint64,
53 2 : ) uint64 {
54 2 : v := uint64(25 * targetFileSize)
55 2 :
56 2 : // Never expand a compaction beyond half the available capacity, divided
57 2 : // by the maximum number of concurrent compactions. Each of the concurrent
58 2 : // compactions may expand up to this limit, so this attempts to limit
59 2 : // compactions to half of available disk space. Note that this will not
60 2 : // prevent compaction picking from pursuing compactions that are larger
61 2 : // than this threshold before expansion.
62 2 : //
63 2 : // NB: this heuristic is an approximation since we may run more compactions
64 2 : // than the upper concurrency limit.
65 2 : _, maxConcurrency := opts.CompactionConcurrencyRange()
66 2 : diskMax := (availBytes / 2) / uint64(maxConcurrency)
67 2 : if v > diskMax {
68 1 : v = diskMax
69 1 : }
70 2 : return v
71 : }
72 :
73 : // maxGrandparentOverlapBytes is the maximum bytes of overlap with level+1
74 : // before we stop building a single file in a level-1 to level compaction.
75 2 : func maxGrandparentOverlapBytes(targetFileSize int64) uint64 {
76 2 : return uint64(10 * targetFileSize)
77 2 : }
78 :
79 : // maxReadCompactionBytes is used to prevent read compactions which
80 : // are too wide.
81 2 : func maxReadCompactionBytes(targetFileSize int64) uint64 {
82 2 : return uint64(10 * targetFileSize)
83 2 : }
84 :
85 : // noCloseIter wraps around a FragmentIterator, intercepting and eliding
86 : // calls to Close. It is used during compaction to ensure that rangeDelIters
87 : // are not closed prematurely.
88 : type noCloseIter struct {
89 : keyspan.FragmentIterator
90 : }
91 :
92 2 : func (i *noCloseIter) Close() {}
93 :
94 : type compactionLevel struct {
95 : level int
96 : files manifest.LevelSlice
97 : // l0SublevelInfo contains information about L0 sublevels being compacted.
98 : // It's only set for the start level of a compaction starting out of L0 and
99 : // is nil for all other compactions.
100 : l0SublevelInfo []sublevelInfo
101 : }
102 :
103 2 : func (cl compactionLevel) Clone() compactionLevel {
104 2 : newCL := compactionLevel{
105 2 : level: cl.level,
106 2 : files: cl.files,
107 2 : }
108 2 : return newCL
109 2 : }
110 1 : func (cl compactionLevel) String() string {
111 1 : return fmt.Sprintf(`Level %d, Files %s`, cl.level, cl.files)
112 1 : }
113 :
114 : // compactionWritable is a objstorage.Writable wrapper that, on every write,
115 : // updates a metric in `versions` on bytes written by in-progress compactions so
116 : // far. It also increments a per-compaction `written` atomic int.
117 : type compactionWritable struct {
118 : objstorage.Writable
119 :
120 : versions *versionSet
121 : written *atomic.Int64
122 : }
123 :
124 : // Write is part of the objstorage.Writable interface.
125 2 : func (c *compactionWritable) Write(p []byte) error {
126 2 : if err := c.Writable.Write(p); err != nil {
127 0 : return err
128 0 : }
129 :
130 2 : c.written.Add(int64(len(p)))
131 2 : c.versions.incrementCompactionBytes(int64(len(p)))
132 2 : return nil
133 : }
134 :
135 : type compactionKind int
136 :
137 : const (
138 : compactionKindDefault compactionKind = iota
139 : compactionKindFlush
140 : // compactionKindMove denotes a move compaction where the input file is
141 : // retained and linked in a new level without being obsoleted.
142 : compactionKindMove
143 : // compactionKindCopy denotes a copy compaction where the input file is
144 : // copied byte-by-byte into a new file with a new TableNum in the output level.
145 : compactionKindCopy
146 : // compactionKindDeleteOnly denotes a compaction that only deletes input
147 : // files. It can occur when wide range tombstones completely contain sstables.
148 : compactionKindDeleteOnly
149 : compactionKindElisionOnly
150 : compactionKindRead
151 : compactionKindTombstoneDensity
152 : compactionKindRewrite
153 : compactionKindIngestedFlushable
154 : compactionKindBlobFileRewrite
155 : )
156 :
157 2 : func (k compactionKind) String() string {
158 2 : switch k {
159 2 : case compactionKindDefault:
160 2 : return "default"
161 0 : case compactionKindFlush:
162 0 : return "flush"
163 2 : case compactionKindMove:
164 2 : return "move"
165 2 : case compactionKindDeleteOnly:
166 2 : return "delete-only"
167 2 : case compactionKindElisionOnly:
168 2 : return "elision-only"
169 1 : case compactionKindRead:
170 1 : return "read"
171 2 : case compactionKindTombstoneDensity:
172 2 : return "tombstone-density"
173 2 : case compactionKindRewrite:
174 2 : return "rewrite"
175 0 : case compactionKindIngestedFlushable:
176 0 : return "ingested-flushable"
177 2 : case compactionKindCopy:
178 2 : return "copy"
179 0 : case compactionKindBlobFileRewrite:
180 0 : return "blob-file-rewrite"
181 : }
182 0 : return "?"
183 : }
184 :
185 : // compactingOrFlushing returns "flushing" if the compaction kind is a flush,
186 : // otherwise it returns "compacting".
187 2 : func (k compactionKind) compactingOrFlushing() string {
188 2 : if k == compactionKindFlush {
189 2 : return "flushing"
190 2 : }
191 2 : return "compacting"
192 : }
193 :
194 : type compaction interface {
195 : AddInProgressLocked(*DB)
196 : BeganAt() time.Time
197 : Bounds() *base.UserKeyBounds
198 : Cancel()
199 : Execute(JobID, *DB) error
200 : GrantHandle() CompactionGrantHandle
201 : Info() compactionInfo
202 : IsDownload() bool
203 : IsFlush() bool
204 : PprofLabels(UserKeyCategories) pprof.LabelSet
205 : RecordError(*problemspans.ByLevel, error)
206 : Tables() iter.Seq2[int, *manifest.TableMetadata]
207 : VersionEditApplied() bool
208 : }
209 :
210 : // tableCompaction is a table compaction from one level to the next, starting
211 : // from a given version. It implements the compaction interface.
212 : type tableCompaction struct {
213 : // cancel is a bool that can be used by other goroutines to signal a compaction
214 : // to cancel, such as if a conflicting excise operation raced it to manifest
215 : // application. Only holders of the manifest lock will write to this atomic.
216 : cancel atomic.Bool
217 : // kind indicates the kind of compaction. Different compaction kinds have
218 : // different semantics and mechanics. Some may have additional fields.
219 : kind compactionKind
220 : // isDownload is true if this compaction was started as part of a Download
221 : // operation. In this case kind is compactionKindCopy or
222 : // compactionKindRewrite.
223 : isDownload bool
224 :
225 : comparer *base.Comparer
226 : logger Logger
227 : version *manifest.Version
228 : // versionEditApplied is set to true when a compaction has completed and the
229 : // resulting version has been installed (if successful), but the compaction
230 : // goroutine is still cleaning up (eg, deleting obsolete files).
231 : versionEditApplied bool
232 : // getValueSeparation constructs a compact.ValueSeparation for use in a
233 : // compaction. It implements heuristics around choosing whether a compaction
234 : // should:
235 : //
236 : // a) preserve existing blob references: The compaction does not write any
237 : // new blob files, but propagates existing references to blob files.This
238 : // conserves write bandwidth by avoiding rewriting the referenced values. It
239 : // also reduces the locality of the referenced values which can reduce scan
240 : // performance because a scan must load values from more unique blob files.
241 : // It can also delay reclamation of disk space if some of the references to
242 : // blob values are elided by the compaction, increasing space amplification.
243 : //
244 : // b) rewrite blob files: The compaction will write eligible values to new
245 : // blob files. This consumes more write bandwidth because all values are
246 : // rewritten. However it restores locality.
247 : getValueSeparation func(JobID, *tableCompaction, sstable.TableFormat) compact.ValueSeparation
248 :
249 : // startLevel is the level that is being compacted. Inputs from startLevel
250 : // and outputLevel will be merged to produce a set of outputLevel files.
251 : startLevel *compactionLevel
252 :
253 : // outputLevel is the level that files are being produced in. outputLevel is
254 : // equal to startLevel+1 except when:
255 : // - if startLevel is 0, the output level equals compactionPicker.baseLevel().
256 : // - in multilevel compaction, the output level is the lowest level involved in
257 : // the compaction
258 : // A compaction's outputLevel is nil for delete-only compactions.
259 : outputLevel *compactionLevel
260 :
261 : // extraLevels point to additional levels in between the input and output
262 : // levels that get compacted in multilevel compactions
263 : extraLevels []*compactionLevel
264 :
265 : inputs []compactionLevel
266 :
267 : // maxOutputFileSize is the maximum size of an individual table created
268 : // during compaction.
269 : maxOutputFileSize uint64
270 : // maxOverlapBytes is the maximum number of bytes of overlap allowed for a
271 : // single output table with the tables in the grandparent level.
272 : maxOverlapBytes uint64
273 :
274 : // The boundaries of the input data.
275 : bounds base.UserKeyBounds
276 :
277 : // grandparents are the tables in level+2 that overlap with the files being
278 : // compacted. Used to determine output table boundaries. Do not assume that the actual files
279 : // in the grandparent when this compaction finishes will be the same.
280 : grandparents manifest.LevelSlice
281 :
282 : delElision compact.TombstoneElision
283 : rangeKeyElision compact.TombstoneElision
284 :
285 : // deleteOnly contains information specific to compactions with kind
286 : // compactionKindDeleteOnly. A delete-only compaction is a special
287 : // compaction that does not merge or write sstables. Instead, it only
288 : // performs deletions either through removing whole sstables from the LSM or
289 : // virtualizing them into virtual sstables.
290 : deleteOnly struct {
291 : // hints are collected by the table stats collector and describe range
292 : // deletions and the files containing keys deleted by them.
293 : hints []deleteCompactionHint
294 : // exciseEnabled is set to true if this compaction is allowed to excise
295 : // files. If false, the compaction will only remove whole sstables that
296 : // are wholly contained within the bounds of range deletions.
297 : exciseEnabled bool
298 : }
299 : // flush contains information specific to flushes (compactionKindFlush and
300 : // compactionKindIngestedFlushable). A flush is modeled by a compaction
301 : // because it has similar mechanics to a default compaction.
302 : flush struct {
303 : // flushables contains the flushables (aka memtables, large batches,
304 : // flushable ingestions, etc) that are being flushed.
305 : flushables flushableList
306 : // Boundaries at which sstables flushed to L0 should be split.
307 : // Determined by L0Sublevels. If nil, ignored.
308 : l0Limits [][]byte
309 : }
310 : // iterationState contains state used during compaction iteration.
311 : iterationState struct {
312 : // bufferPool is a pool of buffers used when reading blocks. Compactions
313 : // do not populate the block cache under the assumption that the blocks
314 : // we read will soon be irrelevant when their containing sstables are
315 : // removed from the LSM.
316 : bufferPool sstable.BufferPool
317 : // keyspanIterClosers is a list of fragment iterators to close when the
318 : // compaction finishes. As iteration opens new keyspan iterators,
319 : // elements are appended. Keyspan iterators must remain open for the
320 : // lifetime of the compaction, so they're accumulated here. When the
321 : // compaction finishes, all the underlying keyspan iterators are closed.
322 : keyspanIterClosers []*noCloseIter
323 : // valueFetcher is used to fetch values from blob files. It's propagated
324 : // down the iterator tree through the internal iterator options.
325 : valueFetcher blob.ValueFetcher
326 : }
327 : // metrics encapsulates various metrics collected during a compaction.
328 : metrics compactionMetrics
329 :
330 : grantHandle CompactionGrantHandle
331 :
332 : tableFormat sstable.TableFormat
333 : objCreateOpts objstorage.CreateOptions
334 : }
335 :
336 : // Assert that tableCompaction implements the compaction interface.
337 : var _ compaction = (*tableCompaction)(nil)
338 :
339 2 : func (c *tableCompaction) AddInProgressLocked(d *DB) {
340 2 : d.mu.compact.inProgress[c] = struct{}{}
341 2 : var isBase, isIntraL0 bool
342 2 : for _, cl := range c.inputs {
343 2 : for f := range cl.files.All() {
344 2 : if f.IsCompacting() {
345 0 : d.opts.Logger.Fatalf("L%d->L%d: %s already being compacted", c.startLevel.level, c.outputLevel.level, f.TableNum)
346 0 : }
347 2 : f.SetCompactionState(manifest.CompactionStateCompacting)
348 2 : if c.startLevel != nil && c.outputLevel != nil && c.startLevel.level == 0 {
349 2 : if c.outputLevel.level == 0 {
350 2 : f.IsIntraL0Compacting = true
351 2 : isIntraL0 = true
352 2 : } else {
353 2 : isBase = true
354 2 : }
355 : }
356 : }
357 : }
358 :
359 2 : if isIntraL0 || isBase {
360 2 : l0Inputs := []manifest.LevelSlice{c.startLevel.files}
361 2 : if isIntraL0 {
362 2 : l0Inputs = append(l0Inputs, c.outputLevel.files)
363 2 : }
364 2 : if err := d.mu.versions.latest.l0Organizer.UpdateStateForStartedCompaction(l0Inputs, isBase); err != nil {
365 0 : d.opts.Logger.Fatalf("could not update state for compaction: %s", err)
366 0 : }
367 : }
368 : }
369 :
370 2 : func (c *tableCompaction) BeganAt() time.Time { return c.metrics.beganAt }
371 2 : func (c *tableCompaction) Bounds() *base.UserKeyBounds { return &c.bounds }
372 2 : func (c *tableCompaction) Cancel() { c.cancel.Store(true) }
373 :
374 2 : func (c *tableCompaction) Execute(jobID JobID, d *DB) error {
375 2 : c.grantHandle.Started()
376 2 : err := d.compact1(jobID, c)
377 2 : // The version stored in the compaction is ref'd when the compaction is
378 2 : // created. We're responsible for un-refing it when the compaction is
379 2 : // complete.
380 2 : if c.version != nil {
381 2 : c.version.UnrefLocked()
382 2 : }
383 2 : return err
384 : }
385 :
386 1 : func (c *tableCompaction) RecordError(problemSpans *problemspans.ByLevel, err error) {
387 1 : // Record problem spans for a short duration, unless the error is a
388 1 : // corruption.
389 1 : expiration := 30 * time.Second
390 1 : if IsCorruptionError(err) {
391 1 : // TODO(radu): ideally, we should be using the corruption reporting
392 1 : // mechanism which has a tighter span for the corruption. We would need to
393 1 : // somehow plumb the level of the file.
394 1 : expiration = 5 * time.Minute
395 1 : }
396 :
397 1 : for i := range c.inputs {
398 1 : level := c.inputs[i].level
399 1 : if level == 0 {
400 1 : // We do not set problem spans on L0, as they could block flushes.
401 1 : continue
402 : }
403 1 : it := c.inputs[i].files.Iter()
404 1 : for f := it.First(); f != nil; f = it.Next() {
405 1 : problemSpans.Add(level, f.UserKeyBounds(), expiration)
406 1 : }
407 : }
408 : }
409 :
410 2 : func (c *tableCompaction) GrantHandle() CompactionGrantHandle { return c.grantHandle }
411 2 : func (c *tableCompaction) IsDownload() bool { return c.isDownload }
412 2 : func (c *tableCompaction) IsFlush() bool { return len(c.flush.flushables) > 0 }
413 2 : func (c *tableCompaction) Info() compactionInfo {
414 2 : info := compactionInfo{
415 2 : versionEditApplied: c.versionEditApplied,
416 2 : kind: c.kind,
417 2 : inputs: c.inputs,
418 2 : bounds: &c.bounds,
419 2 : outputLevel: -1,
420 2 : }
421 2 : if c.outputLevel != nil {
422 2 : info.outputLevel = c.outputLevel.level
423 2 : }
424 2 : return info
425 : }
426 2 : func (c *tableCompaction) PprofLabels(kc UserKeyCategories) pprof.LabelSet {
427 2 : activity := "compact"
428 2 : if len(c.flush.flushables) != 0 {
429 0 : activity = "flush"
430 0 : }
431 2 : level := "L?"
432 2 : // Delete-only compactions don't have an output level.
433 2 : if c.outputLevel != nil {
434 2 : level = fmt.Sprintf("L%d", c.outputLevel.level)
435 2 : }
436 2 : if kc.Len() > 0 {
437 0 : cat := kc.CategorizeKeyRange(c.bounds.Start, c.bounds.End.Key)
438 0 : return pprof.Labels("pebble", activity, "output-level", level, "key-type", cat)
439 0 : }
440 2 : return pprof.Labels("pebble", activity, "output-level", level)
441 : }
442 :
443 2 : func (c *tableCompaction) Tables() iter.Seq2[int, *manifest.TableMetadata] {
444 2 : return func(yield func(int, *manifest.TableMetadata) bool) {
445 2 : for _, cl := range c.inputs {
446 2 : for f := range cl.files.All() {
447 2 : if !yield(cl.level, f) {
448 2 : return
449 2 : }
450 : }
451 : }
452 : }
453 : }
454 :
455 2 : func (c *tableCompaction) VersionEditApplied() bool { return c.versionEditApplied }
456 :
457 : // compactionMetrics contians metrics surrounding a compaction.
458 : type compactionMetrics struct {
459 : // beganAt is the time when the compaction began.
460 : beganAt time.Time
461 : // bytesWritten contains the number of bytes that have been written to
462 : // outputs. It's updated whenever the compaction outputs'
463 : // objstorage.Writables receive new writes. See newCompactionOutputObj.
464 : bytesWritten atomic.Int64
465 : // internalIterStats contains statistics from the internal iterators used by
466 : // the compaction.
467 : //
468 : // TODO(jackson): Use these to power the compaction BytesRead metric.
469 : internalIterStats base.InternalIteratorStats
470 : // perLevel contains metrics for each level involved in the compaction.
471 : perLevel levelMetricsDelta
472 : // picker contains metrics from the compaction picker when the compaction
473 : // was picked.
474 : picker pickedCompactionMetrics
475 : }
476 :
477 : // inputLargestSeqNumAbsolute returns the maximum LargestSeqNumAbsolute of any
478 : // input sstables.
479 2 : func (c *tableCompaction) inputLargestSeqNumAbsolute() base.SeqNum {
480 2 : var seqNum base.SeqNum
481 2 : for _, cl := range c.inputs {
482 2 : for m := range cl.files.All() {
483 2 : seqNum = max(seqNum, m.LargestSeqNumAbsolute)
484 2 : }
485 : }
486 2 : return seqNum
487 : }
488 :
489 2 : func (c *tableCompaction) makeInfo(jobID JobID) CompactionInfo {
490 2 : info := CompactionInfo{
491 2 : JobID: int(jobID),
492 2 : Reason: c.kind.String(),
493 2 : Input: make([]LevelInfo, 0, len(c.inputs)),
494 2 : Annotations: []string{},
495 2 : }
496 2 : if c.isDownload {
497 2 : info.Reason = "download," + info.Reason
498 2 : }
499 2 : for _, cl := range c.inputs {
500 2 : inputInfo := LevelInfo{Level: cl.level, Tables: nil}
501 2 : for m := range cl.files.All() {
502 2 : inputInfo.Tables = append(inputInfo.Tables, m.TableInfo())
503 2 : }
504 2 : info.Input = append(info.Input, inputInfo)
505 : }
506 2 : if c.outputLevel != nil {
507 2 : info.Output.Level = c.outputLevel.level
508 2 :
509 2 : // If there are no inputs from the output level (eg, a move
510 2 : // compaction), add an empty LevelInfo to info.Input.
511 2 : if len(c.inputs) > 0 && c.inputs[len(c.inputs)-1].level != c.outputLevel.level {
512 0 : info.Input = append(info.Input, LevelInfo{Level: c.outputLevel.level})
513 0 : }
514 2 : } else {
515 2 : // For a delete-only compaction, set the output level to L6. The
516 2 : // output level is not meaningful here, but complicating the
517 2 : // info.Output interface with a pointer doesn't seem worth the
518 2 : // semantic distinction.
519 2 : info.Output.Level = numLevels - 1
520 2 : }
521 :
522 2 : for i, score := range c.metrics.picker.scores {
523 2 : info.Input[i].Score = score
524 2 : }
525 2 : info.SingleLevelOverlappingRatio = c.metrics.picker.singleLevelOverlappingRatio
526 2 : info.MultiLevelOverlappingRatio = c.metrics.picker.multiLevelOverlappingRatio
527 2 : if len(info.Input) > 2 {
528 2 : info.Annotations = append(info.Annotations, "multilevel")
529 2 : }
530 2 : return info
531 : }
532 :
533 : type getValueSeparation func(JobID, *tableCompaction, sstable.TableFormat) compact.ValueSeparation
534 :
535 : // newCompaction constructs a compaction from the provided picked compaction.
536 : //
537 : // The compaction is created with a reference to its version that must be
538 : // released when the compaction is complete.
539 : func newCompaction(
540 : pc *pickedTableCompaction,
541 : opts *Options,
542 : beganAt time.Time,
543 : provider objstorage.Provider,
544 : grantHandle CompactionGrantHandle,
545 : tableFormat sstable.TableFormat,
546 : getValueSeparation getValueSeparation,
547 2 : ) *tableCompaction {
548 2 : c := &tableCompaction{
549 2 : kind: compactionKindDefault,
550 2 : comparer: opts.Comparer,
551 2 : inputs: pc.inputs,
552 2 : bounds: pc.bounds,
553 2 : logger: opts.Logger,
554 2 : version: pc.version,
555 2 : getValueSeparation: getValueSeparation,
556 2 : maxOutputFileSize: pc.maxOutputFileSize,
557 2 : maxOverlapBytes: pc.maxOverlapBytes,
558 2 : metrics: compactionMetrics{
559 2 : beganAt: beganAt,
560 2 : picker: pc.pickerMetrics,
561 2 : },
562 2 : grantHandle: grantHandle,
563 2 : tableFormat: tableFormat,
564 2 : }
565 2 : // Acquire a reference to the version to ensure that files and in-memory
566 2 : // version state necessary for reading files remain available. Ignoring
567 2 : // excises, this isn't strictly necessary for reading the sstables that are
568 2 : // inputs to the compaction because those files are 'marked as compacting'
569 2 : // and shouldn't be subject to any competing compactions. However with
570 2 : // excises, a concurrent excise may remove a compaction's file from the
571 2 : // Version and then cancel the compaction. The file shouldn't be physically
572 2 : // removed until the cancelled compaction stops reading it.
573 2 : //
574 2 : // Additionally, we need any blob files referenced by input sstables to
575 2 : // remain available, even if the blob file is rewritten. Maintaining a
576 2 : // reference ensures that all these files remain available for the
577 2 : // compaction's reads.
578 2 : c.version.Ref()
579 2 :
580 2 : c.startLevel = &c.inputs[0]
581 2 : if pc.startLevel.l0SublevelInfo != nil {
582 2 : c.startLevel.l0SublevelInfo = pc.startLevel.l0SublevelInfo
583 2 : }
584 :
585 2 : c.outputLevel = &c.inputs[len(c.inputs)-1]
586 2 :
587 2 : if len(pc.inputs) > 2 {
588 2 : // TODO(xinhaoz): Look into removing extraLevels on the compaction struct.
589 2 : c.extraLevels = make([]*compactionLevel, 0, len(pc.inputs)-2)
590 2 : for i := 1; i < len(pc.inputs)-1; i++ {
591 2 : c.extraLevels = append(c.extraLevels, &c.inputs[i])
592 2 : }
593 : }
594 : // Compute the set of outputLevel+1 files that overlap this compaction (these
595 : // are the grandparent sstables).
596 2 : if c.outputLevel.level+1 < numLevels {
597 2 : c.grandparents = c.version.Overlaps(c.outputLevel.level+1, c.bounds)
598 2 : }
599 2 : c.delElision, c.rangeKeyElision = compact.SetupTombstoneElision(
600 2 : c.comparer.Compare, c.version, pc.l0Organizer, c.outputLevel.level, c.bounds,
601 2 : )
602 2 : c.kind = pc.kind
603 2 :
604 2 : preferSharedStorage := tableFormat >= FormatMinForSharedObjects.MaxTableFormat() &&
605 2 : remote.ShouldCreateShared(opts.Experimental.CreateOnShared, c.outputLevel.level)
606 2 : c.maybeSwitchToMoveOrCopy(preferSharedStorage, provider)
607 2 : c.objCreateOpts = objstorage.CreateOptions{
608 2 : PreferSharedStorage: preferSharedStorage,
609 2 : WriteCategory: getDiskWriteCategoryForCompaction(opts, c.kind),
610 2 : }
611 2 : if preferSharedStorage {
612 2 : c.getValueSeparation = neverSeparateValues
613 2 : }
614 :
615 2 : return c
616 : }
617 :
618 : // maybeSwitchToMoveOrCopy decides if the compaction can be changed into a move
619 : // or copy compaction, in which case c.kind is updated.
620 : func (c *tableCompaction) maybeSwitchToMoveOrCopy(
621 : preferSharedStorage bool, provider objstorage.Provider,
622 2 : ) {
623 2 : // Only non-multi-level compactions with a single input file can be
624 2 : // considered.
625 2 : if c.startLevel.files.Len() != 1 || !c.outputLevel.files.Empty() || c.hasExtraLevelData() {
626 2 : return
627 2 : }
628 :
629 : // In addition to the default compaction, we also check whether a tombstone
630 : // density compaction can be optimized into a move compaction. However, we
631 : // want to avoid performing a move compaction into the lowest level, since the
632 : // goal there is to actually remove the tombstones.
633 : //
634 : // Tombstone density compaction is meant to address cases where tombstones
635 : // don't reclaim much space but are still expensive to scan over. We can only
636 : // remove the tombstones once there's nothing at all underneath them.
637 2 : switch c.kind {
638 2 : case compactionKindDefault:
639 : // Proceed.
640 2 : case compactionKindTombstoneDensity:
641 2 : // Tombstone density compaction can be optimized into a move compaction.
642 2 : // However, we want to avoid performing a move compaction into the lowest
643 2 : // level, since the goal there is to actually remove the tombstones; even if
644 2 : // they don't prevent a lot of space from being reclaimed, tombstones can
645 2 : // still be expensive to scan over.
646 2 : if c.outputLevel.level == numLevels-1 {
647 2 : return
648 2 : }
649 2 : default:
650 2 : // Other compaction kinds not supported.
651 2 : return
652 : }
653 :
654 : // We avoid a move or copy if there is lots of overlapping grandparent data.
655 : // Otherwise, the move could create a parent file that will require a very
656 : // expensive merge later on.
657 2 : if c.grandparents.AggregateSizeSum() > c.maxOverlapBytes {
658 1 : return
659 1 : }
660 :
661 2 : iter := c.startLevel.files.Iter()
662 2 : meta := iter.First()
663 2 :
664 2 : // We should always be passed a provider, except in some unit tests.
665 2 : isRemote := provider != nil && !objstorage.IsLocalTable(provider, meta.TableBacking.DiskFileNum)
666 2 :
667 2 : // Shared and external tables can always be moved. We can also move a local
668 2 : // table unless we need the result to be on shared storage.
669 2 : if isRemote || !preferSharedStorage {
670 2 : c.kind = compactionKindMove
671 2 : return
672 2 : }
673 :
674 : // We can rewrite the table (regular compaction) or we can use a copy compaction.
675 2 : switch {
676 1 : case meta.Virtual:
677 : // We want to avoid a copy compaction if the table is virtual, as we may end
678 : // up copying a lot more data than necessary.
679 2 : case meta.BlobReferenceDepth != 0:
680 : // We also want to avoid copy compactions for tables with blob references,
681 : // as we currently lack a mechanism to propagate blob references along with
682 : // the sstable.
683 2 : default:
684 2 : c.kind = compactionKindCopy
685 : }
686 : }
687 :
688 : // newDeleteOnlyCompaction constructs a delete-only compaction from the provided
689 : // inputs.
690 : //
691 : // The compaction is created with a reference to its version that must be
692 : // released when the compaction is complete.
693 : func newDeleteOnlyCompaction(
694 : opts *Options,
695 : cur *manifest.Version,
696 : inputs []compactionLevel,
697 : beganAt time.Time,
698 : hints []deleteCompactionHint,
699 : exciseEnabled bool,
700 2 : ) *tableCompaction {
701 2 : c := &tableCompaction{
702 2 : kind: compactionKindDeleteOnly,
703 2 : comparer: opts.Comparer,
704 2 : logger: opts.Logger,
705 2 : version: cur,
706 2 : inputs: inputs,
707 2 : grantHandle: noopGrantHandle{},
708 2 : metrics: compactionMetrics{
709 2 : beganAt: beganAt,
710 2 : },
711 2 : }
712 2 : c.deleteOnly.hints = hints
713 2 : c.deleteOnly.exciseEnabled = exciseEnabled
714 2 : // Acquire a reference to the version to ensure that files and in-memory
715 2 : // version state necessary for reading files remain available. Ignoring
716 2 : // excises, this isn't strictly necessary for reading the sstables that are
717 2 : // inputs to the compaction because those files are 'marked as compacting'
718 2 : // and shouldn't be subject to any competing compactions. However with
719 2 : // excises, a concurrent excise may remove a compaction's file from the
720 2 : // Version and then cancel the compaction. The file shouldn't be physically
721 2 : // removed until the cancelled compaction stops reading it.
722 2 : //
723 2 : // Additionally, we need any blob files referenced by input sstables to
724 2 : // remain available, even if the blob file is rewritten. Maintaining a
725 2 : // reference ensures that all these files remain available for the
726 2 : // compaction's reads.
727 2 : c.version.Ref()
728 2 :
729 2 : // Set c.smallest, c.largest.
730 2 : cmp := opts.Comparer.Compare
731 2 : for _, in := range inputs {
732 2 : c.bounds = manifest.ExtendKeyRange(cmp, c.bounds, in.files.All())
733 2 : }
734 2 : return c
735 : }
736 :
737 2 : func adjustGrandparentOverlapBytesForFlush(c *tableCompaction, flushingBytes uint64) {
738 2 : // Heuristic to place a lower bound on compaction output file size
739 2 : // caused by Lbase. Prior to this heuristic we have observed an L0 in
740 2 : // production with 310K files of which 290K files were < 10KB in size.
741 2 : // Our hypothesis is that it was caused by L1 having 2600 files and
742 2 : // ~10GB, such that each flush got split into many tiny files due to
743 2 : // overlapping with most of the files in Lbase.
744 2 : //
745 2 : // The computation below is general in that it accounts
746 2 : // for flushing different volumes of data (e.g. we may be flushing
747 2 : // many memtables). For illustration, we consider the typical
748 2 : // example of flushing a 64MB memtable. So 12.8MB output,
749 2 : // based on the compression guess below. If the compressed bytes
750 2 : // guess is an over-estimate we will end up with smaller files,
751 2 : // and if an under-estimate we will end up with larger files.
752 2 : // With a 2MB target file size, 7 files. We are willing to accept
753 2 : // 4x the number of files, if it results in better write amplification
754 2 : // when later compacting to Lbase, i.e., ~450KB files (target file
755 2 : // size / 4).
756 2 : //
757 2 : // Note that this is a pessimistic heuristic in that
758 2 : // fileCountUpperBoundDueToGrandparents could be far from the actual
759 2 : // number of files produced due to the grandparent limits. For
760 2 : // example, in the extreme, consider a flush that overlaps with 1000
761 2 : // files in Lbase f0...f999, and the initially calculated value of
762 2 : // maxOverlapBytes will cause splits at f10, f20,..., f990, which
763 2 : // means an upper bound file count of 100 files. Say the input bytes
764 2 : // in the flush are such that acceptableFileCount=10. We will fatten
765 2 : // up maxOverlapBytes by 10x to ensure that the upper bound file count
766 2 : // drops to 10. However, it is possible that in practice, even without
767 2 : // this change, we would have produced no more than 10 files, and that
768 2 : // this change makes the files unnecessarily wide. Say the input bytes
769 2 : // are distributed such that 10% are in f0...f9, 10% in f10...f19, ...
770 2 : // 10% in f80...f89 and 10% in f990...f999. The original value of
771 2 : // maxOverlapBytes would have actually produced only 10 sstables. But
772 2 : // by increasing maxOverlapBytes by 10x, we may produce 1 sstable that
773 2 : // spans f0...f89, i.e., a much wider sstable than necessary.
774 2 : //
775 2 : // We could produce a tighter estimate of
776 2 : // fileCountUpperBoundDueToGrandparents if we had knowledge of the key
777 2 : // distribution of the flush. The 4x multiplier mentioned earlier is
778 2 : // a way to try to compensate for this pessimism.
779 2 : //
780 2 : // TODO(sumeer): we don't have compression info for the data being
781 2 : // flushed, but it is likely that existing files that overlap with
782 2 : // this flush in Lbase are representative wrt compression ratio. We
783 2 : // could store the uncompressed size in TableMetadata and estimate
784 2 : // the compression ratio.
785 2 : const approxCompressionRatio = 0.2
786 2 : approxOutputBytes := approxCompressionRatio * float64(flushingBytes)
787 2 : approxNumFilesBasedOnTargetSize :=
788 2 : int(math.Ceil(approxOutputBytes / float64(c.maxOutputFileSize)))
789 2 : acceptableFileCount := float64(4 * approxNumFilesBasedOnTargetSize)
790 2 : // The byte calculation is linear in numGrandparentFiles, but we will
791 2 : // incur this linear cost in compact.Runner.TableSplitLimit() too, so we are
792 2 : // also willing to pay it now. We could approximate this cheaply by using the
793 2 : // mean file size of Lbase.
794 2 : grandparentFileBytes := c.grandparents.AggregateSizeSum()
795 2 : fileCountUpperBoundDueToGrandparents :=
796 2 : float64(grandparentFileBytes) / float64(c.maxOverlapBytes)
797 2 : if fileCountUpperBoundDueToGrandparents > acceptableFileCount {
798 2 : c.maxOverlapBytes = uint64(
799 2 : float64(c.maxOverlapBytes) *
800 2 : (fileCountUpperBoundDueToGrandparents / acceptableFileCount))
801 2 : }
802 : }
803 :
804 : // newFlush creates the state necessary for a flush (modeled with the compaction
805 : // struct).
806 : //
807 : // newFlush takes the current Version in order to populate grandparent flushing
808 : // limits, but it does not reference the version.
809 : //
810 : // TODO(jackson): Consider maintaining a reference to the version anyways since
811 : // in the future in-memory Version state may only be available while a Version
812 : // is referenced (eg, if we start recycling B-Tree nodes once they're no longer
813 : // referenced). There's subtlety around unref'ing the version at the right
814 : // moment, so we defer it for now.
815 : func newFlush(
816 : opts *Options,
817 : cur *manifest.Version,
818 : l0Organizer *manifest.L0Organizer,
819 : baseLevel int,
820 : flushing flushableList,
821 : beganAt time.Time,
822 : tableFormat sstable.TableFormat,
823 : getValueSeparation getValueSeparation,
824 2 : ) (*tableCompaction, error) {
825 2 : c := &tableCompaction{
826 2 : kind: compactionKindFlush,
827 2 : comparer: opts.Comparer,
828 2 : logger: opts.Logger,
829 2 : inputs: []compactionLevel{{level: -1}, {level: 0}},
830 2 : getValueSeparation: getValueSeparation,
831 2 : maxOutputFileSize: math.MaxUint64,
832 2 : maxOverlapBytes: math.MaxUint64,
833 2 : grantHandle: noopGrantHandle{},
834 2 : tableFormat: tableFormat,
835 2 : metrics: compactionMetrics{
836 2 : beganAt: beganAt,
837 2 : },
838 2 : }
839 2 : c.flush.flushables = flushing
840 2 : c.flush.l0Limits = l0Organizer.FlushSplitKeys()
841 2 : c.startLevel = &c.inputs[0]
842 2 : c.outputLevel = &c.inputs[1]
843 2 : if len(flushing) > 0 {
844 2 : if _, ok := flushing[0].flushable.(*ingestedFlushable); ok {
845 2 : if len(flushing) != 1 {
846 0 : panic("pebble: ingestedFlushable must be flushed one at a time.")
847 : }
848 2 : c.kind = compactionKindIngestedFlushable
849 2 : return c, nil
850 2 : } else {
851 2 : // Make sure there's no ingestedFlushable after the first flushable
852 2 : // in the list.
853 2 : for _, f := range c.flush.flushables[1:] {
854 2 : if _, ok := f.flushable.(*ingestedFlushable); ok {
855 0 : panic("pebble: flushables shouldn't contain ingestedFlushable")
856 : }
857 : }
858 : }
859 : }
860 :
861 2 : preferSharedStorage := tableFormat >= FormatMinForSharedObjects.MaxTableFormat() &&
862 2 : remote.ShouldCreateShared(opts.Experimental.CreateOnShared, c.outputLevel.level)
863 2 : c.objCreateOpts = objstorage.CreateOptions{
864 2 : PreferSharedStorage: preferSharedStorage,
865 2 : WriteCategory: getDiskWriteCategoryForCompaction(opts, c.kind),
866 2 : }
867 2 : if preferSharedStorage {
868 2 : c.getValueSeparation = neverSeparateValues
869 2 : }
870 :
871 2 : cmp := c.comparer.Compare
872 2 : updatePointBounds := func(iter internalIterator) {
873 2 : if kv := iter.First(); kv != nil {
874 2 : if c.bounds.Start == nil || cmp(c.bounds.Start, kv.K.UserKey) > 0 {
875 2 : c.bounds.Start = slices.Clone(kv.K.UserKey)
876 2 : }
877 : }
878 2 : if kv := iter.Last(); kv != nil {
879 2 : if c.bounds.End.Key == nil || !c.bounds.End.IsUpperBoundForInternalKey(cmp, kv.K) {
880 2 : c.bounds.End = base.UserKeyExclusiveIf(slices.Clone(kv.K.UserKey), kv.K.IsExclusiveSentinel())
881 2 : }
882 : }
883 : }
884 :
885 2 : updateRangeBounds := func(iter keyspan.FragmentIterator) error {
886 2 : // File bounds require s != nil && !s.Empty(). We only need to check for
887 2 : // s != nil here, as the memtable's FragmentIterator would never surface
888 2 : // empty spans.
889 2 : if s, err := iter.First(); err != nil {
890 0 : return err
891 2 : } else if s != nil {
892 2 : c.bounds = c.bounds.Union(cmp, s.Bounds().Clone())
893 2 : }
894 2 : if s, err := iter.Last(); err != nil {
895 0 : return err
896 2 : } else if s != nil {
897 2 : c.bounds = c.bounds.Union(cmp, s.Bounds().Clone())
898 2 : }
899 2 : return nil
900 : }
901 :
902 2 : var flushingBytes uint64
903 2 : for i := range flushing {
904 2 : f := flushing[i]
905 2 : updatePointBounds(f.newIter(nil))
906 2 : if rangeDelIter := f.newRangeDelIter(nil); rangeDelIter != nil {
907 2 : if err := updateRangeBounds(rangeDelIter); err != nil {
908 0 : return nil, err
909 0 : }
910 : }
911 2 : if rangeKeyIter := f.newRangeKeyIter(nil); rangeKeyIter != nil {
912 2 : if err := updateRangeBounds(rangeKeyIter); err != nil {
913 0 : return nil, err
914 0 : }
915 : }
916 2 : flushingBytes += f.inuseBytes()
917 : }
918 :
919 2 : if opts.FlushSplitBytes > 0 {
920 2 : c.maxOutputFileSize = uint64(opts.TargetFileSizes[0])
921 2 : c.maxOverlapBytes = maxGrandparentOverlapBytes(opts.TargetFileSizes[0])
922 2 : c.grandparents = cur.Overlaps(baseLevel, c.bounds)
923 2 : adjustGrandparentOverlapBytesForFlush(c, flushingBytes)
924 2 : }
925 :
926 : // We don't elide tombstones for flushes.
927 2 : c.delElision, c.rangeKeyElision = compact.NoTombstoneElision(), compact.NoTombstoneElision()
928 2 : return c, nil
929 : }
930 :
931 2 : func (c *tableCompaction) hasExtraLevelData() bool {
932 2 : if len(c.extraLevels) == 0 {
933 2 : // not a multi level compaction
934 2 : return false
935 2 : } else if c.extraLevels[0].files.Empty() {
936 2 : // a multi level compaction without data in the intermediate input level;
937 2 : // e.g. for a multi level compaction with levels 4,5, and 6, this could
938 2 : // occur if there is no files to compact in 5, or in 5 and 6 (i.e. a move).
939 2 : return false
940 2 : }
941 2 : return true
942 : }
943 :
944 : // errorOnUserKeyOverlap returns an error if the last two written sstables in
945 : // this compaction have revisions of the same user key present in both sstables,
946 : // when it shouldn't (eg. when splitting flushes).
947 1 : func (c *tableCompaction) errorOnUserKeyOverlap(ve *manifest.VersionEdit) error {
948 1 : if n := len(ve.NewTables); n > 1 {
949 1 : meta := ve.NewTables[n-1].Meta
950 1 : prevMeta := ve.NewTables[n-2].Meta
951 1 : if !prevMeta.Largest().IsExclusiveSentinel() &&
952 1 : c.comparer.Compare(prevMeta.Largest().UserKey, meta.Smallest().UserKey) >= 0 {
953 1 : return errors.Errorf("pebble: compaction split user key across two sstables: %s in %s and %s",
954 1 : prevMeta.Largest().Pretty(c.comparer.FormatKey),
955 1 : prevMeta.TableNum,
956 1 : meta.TableNum)
957 1 : }
958 : }
959 1 : return nil
960 : }
961 :
962 : // allowZeroSeqNum returns true if seqnum's can be zeroed if there are no
963 : // snapshots requiring them to be kept. It performs this determination by
964 : // looking at the TombstoneElision values which are set up based on sstables
965 : // which overlap the bounds of the compaction at a lower level in the LSM.
966 2 : func (c *tableCompaction) allowZeroSeqNum() bool {
967 2 : // TODO(peter): we disable zeroing of seqnums during flushing to match
968 2 : // RocksDB behavior and to avoid generating overlapping sstables during
969 2 : // DB.replayWAL. When replaying WAL files at startup, we flush after each
970 2 : // WAL is replayed building up a single version edit that is
971 2 : // applied. Because we don't apply the version edit after each flush, this
972 2 : // code doesn't know that L0 contains files and zeroing of seqnums should
973 2 : // be disabled. That is fixable, but it seems safer to just match the
974 2 : // RocksDB behavior for now.
975 2 : return len(c.flush.flushables) == 0 && c.delElision.ElidesEverything() && c.rangeKeyElision.ElidesEverything()
976 2 : }
977 :
978 : // newInputIters returns an iterator over all the input tables in a compaction.
979 : func (c *tableCompaction) newInputIters(
980 : newIters tableNewIters, iiopts internalIterOpts,
981 : ) (
982 : pointIter internalIterator,
983 : rangeDelIter, rangeKeyIter keyspan.FragmentIterator,
984 : retErr error,
985 2 : ) {
986 2 : ctx := context.TODO()
987 2 : cmp := c.comparer.Compare
988 2 :
989 2 : // Validate the ordering of compaction input files for defense in depth.
990 2 : if len(c.flush.flushables) == 0 {
991 2 : if c.startLevel.level >= 0 {
992 2 : err := manifest.CheckOrdering(c.comparer, manifest.Level(c.startLevel.level),
993 2 : c.startLevel.files.Iter())
994 2 : if err != nil {
995 1 : return nil, nil, nil, err
996 1 : }
997 : }
998 2 : err := manifest.CheckOrdering(c.comparer, manifest.Level(c.outputLevel.level),
999 2 : c.outputLevel.files.Iter())
1000 2 : if err != nil {
1001 1 : return nil, nil, nil, err
1002 1 : }
1003 2 : if c.startLevel.level == 0 {
1004 2 : if c.startLevel.l0SublevelInfo == nil {
1005 0 : panic("l0SublevelInfo not created for compaction out of L0")
1006 : }
1007 2 : for _, info := range c.startLevel.l0SublevelInfo {
1008 2 : err := manifest.CheckOrdering(c.comparer, info.sublevel, info.Iter())
1009 2 : if err != nil {
1010 1 : return nil, nil, nil, err
1011 1 : }
1012 : }
1013 : }
1014 2 : if len(c.extraLevels) > 0 {
1015 2 : if len(c.extraLevels) > 1 {
1016 0 : panic("n>2 multi level compaction not implemented yet")
1017 : }
1018 2 : interLevel := c.extraLevels[0]
1019 2 : err := manifest.CheckOrdering(c.comparer, manifest.Level(interLevel.level),
1020 2 : interLevel.files.Iter())
1021 2 : if err != nil {
1022 0 : return nil, nil, nil, err
1023 0 : }
1024 : }
1025 : }
1026 :
1027 : // There are three classes of keys that a compaction needs to process: point
1028 : // keys, range deletion tombstones and range keys. Collect all iterators for
1029 : // all these classes of keys from all the levels. We'll aggregate them
1030 : // together farther below.
1031 : //
1032 : // numInputLevels is an approximation of the number of iterator levels. Due
1033 : // to idiosyncrasies in iterator construction, we may (rarely) exceed this
1034 : // initial capacity.
1035 2 : numInputLevels := max(len(c.flush.flushables), len(c.inputs))
1036 2 : iters := make([]internalIterator, 0, numInputLevels)
1037 2 : rangeDelIters := make([]keyspan.FragmentIterator, 0, numInputLevels)
1038 2 : rangeKeyIters := make([]keyspan.FragmentIterator, 0, numInputLevels)
1039 2 :
1040 2 : // If construction of the iterator inputs fails, ensure that we close all
1041 2 : // the consitutent iterators.
1042 2 : defer func() {
1043 2 : if retErr != nil {
1044 1 : for _, iter := range iters {
1045 1 : if iter != nil {
1046 1 : _ = iter.Close()
1047 1 : }
1048 : }
1049 1 : for _, rangeDelIter := range rangeDelIters {
1050 0 : rangeDelIter.Close()
1051 0 : }
1052 : }
1053 : }()
1054 2 : iterOpts := IterOptions{
1055 2 : Category: categoryCompaction,
1056 2 : logger: c.logger,
1057 2 : }
1058 2 :
1059 2 : // Populate iters, rangeDelIters and rangeKeyIters with the appropriate
1060 2 : // constituent iterators. This depends on whether this is a flush or a
1061 2 : // compaction.
1062 2 : if len(c.flush.flushables) != 0 {
1063 2 : // If flushing, we need to build the input iterators over the memtables
1064 2 : // stored in c.flush.flushables.
1065 2 : for _, f := range c.flush.flushables {
1066 2 : iters = append(iters, f.newFlushIter(nil))
1067 2 : rangeDelIter := f.newRangeDelIter(nil)
1068 2 : if rangeDelIter != nil {
1069 2 : rangeDelIters = append(rangeDelIters, rangeDelIter)
1070 2 : }
1071 2 : if rangeKeyIter := f.newRangeKeyIter(nil); rangeKeyIter != nil {
1072 2 : rangeKeyIters = append(rangeKeyIters, rangeKeyIter)
1073 2 : }
1074 : }
1075 2 : } else {
1076 2 : addItersForLevel := func(level *compactionLevel, l manifest.Layer) error {
1077 2 : // Add a *levelIter for point iterators. Because we don't call
1078 2 : // initRangeDel, the levelIter will close and forget the range
1079 2 : // deletion iterator when it steps on to a new file. Surfacing range
1080 2 : // deletions to compactions are handled below.
1081 2 : iters = append(iters, newLevelIter(ctx, iterOpts, c.comparer,
1082 2 : newIters, level.files.Iter(), l, iiopts))
1083 2 : // TODO(jackson): Use keyspanimpl.LevelIter to avoid loading all the range
1084 2 : // deletions into memory upfront. (See #2015, which reverted this.) There
1085 2 : // will be no user keys that are split between sstables within a level in
1086 2 : // Cockroach 23.1, which unblocks this optimization.
1087 2 :
1088 2 : // Add the range deletion iterator for each file as an independent level
1089 2 : // in mergingIter, as opposed to making a levelIter out of those. This
1090 2 : // is safer as levelIter expects all keys coming from underlying
1091 2 : // iterators to be in order. Due to compaction / tombstone writing
1092 2 : // logic in finishOutput(), it is possible for range tombstones to not
1093 2 : // be strictly ordered across all files in one level.
1094 2 : //
1095 2 : // Consider this example from the metamorphic tests (also repeated in
1096 2 : // finishOutput()), consisting of three L3 files with their bounds
1097 2 : // specified in square brackets next to the file name:
1098 2 : //
1099 2 : // ./000240.sst [tmgc#391,MERGE-tmgc#391,MERGE]
1100 2 : // tmgc#391,MERGE [786e627a]
1101 2 : // tmgc-udkatvs#331,RANGEDEL
1102 2 : //
1103 2 : // ./000241.sst [tmgc#384,MERGE-tmgc#384,MERGE]
1104 2 : // tmgc#384,MERGE [666c7070]
1105 2 : // tmgc-tvsalezade#383,RANGEDEL
1106 2 : // tmgc-tvsalezade#331,RANGEDEL
1107 2 : //
1108 2 : // ./000242.sst [tmgc#383,RANGEDEL-tvsalezade#72057594037927935,RANGEDEL]
1109 2 : // tmgc-tvsalezade#383,RANGEDEL
1110 2 : // tmgc#375,SET [72646c78766965616c72776865676e79]
1111 2 : // tmgc-tvsalezade#356,RANGEDEL
1112 2 : //
1113 2 : // Here, the range tombstone in 000240.sst falls "after" one in
1114 2 : // 000241.sst, despite 000240.sst being ordered "before" 000241.sst for
1115 2 : // levelIter's purposes. While each file is still consistent before its
1116 2 : // bounds, it's safer to have all rangedel iterators be visible to
1117 2 : // mergingIter.
1118 2 : iter := level.files.Iter()
1119 2 : for f := iter.First(); f != nil; f = iter.Next() {
1120 2 : rangeDelIter, err := c.newRangeDelIter(ctx, newIters, iter.Take(), iterOpts, iiopts, l)
1121 2 : if err != nil {
1122 1 : // The error will already be annotated with the BackingFileNum, so
1123 1 : // we annotate it with the FileNum.
1124 1 : return errors.Wrapf(err, "pebble: could not open table %s", errors.Safe(f.TableNum))
1125 1 : }
1126 2 : if rangeDelIter == nil {
1127 2 : continue
1128 : }
1129 2 : rangeDelIters = append(rangeDelIters, rangeDelIter)
1130 2 : c.iterationState.keyspanIterClosers = append(c.iterationState.keyspanIterClosers, rangeDelIter)
1131 : }
1132 :
1133 : // Check if this level has any range keys.
1134 2 : hasRangeKeys := false
1135 2 : for f := iter.First(); f != nil; f = iter.Next() {
1136 2 : if f.HasRangeKeys {
1137 2 : hasRangeKeys = true
1138 2 : break
1139 : }
1140 : }
1141 2 : if hasRangeKeys {
1142 2 : newRangeKeyIterWrapper := func(ctx context.Context, file *manifest.TableMetadata, iterOptions keyspan.SpanIterOptions) (keyspan.FragmentIterator, error) {
1143 2 : iters, err := newIters(ctx, file, &iterOpts, iiopts, iterRangeKeys)
1144 2 : if err != nil {
1145 0 : return nil, err
1146 2 : } else if iters.rangeKey == nil {
1147 0 : return emptyKeyspanIter, nil
1148 0 : }
1149 : // Ensure that the range key iter is not closed until the compaction is
1150 : // finished. This is necessary because range key processing
1151 : // requires the range keys to be held in memory for up to the
1152 : // lifetime of the compaction.
1153 2 : noCloseIter := &noCloseIter{iters.rangeKey}
1154 2 : c.iterationState.keyspanIterClosers = append(c.iterationState.keyspanIterClosers, noCloseIter)
1155 2 :
1156 2 : // We do not need to truncate range keys to sstable boundaries, or
1157 2 : // only read within the file's atomic compaction units, unlike with
1158 2 : // range tombstones. This is because range keys were added after we
1159 2 : // stopped splitting user keys across sstables, so all the range keys
1160 2 : // in this sstable must wholly lie within the file's bounds.
1161 2 : return noCloseIter, err
1162 : }
1163 2 : li := keyspanimpl.NewLevelIter(ctx, keyspan.SpanIterOptions{}, cmp,
1164 2 : newRangeKeyIterWrapper, level.files.Iter(), l, manifest.KeyTypeRange)
1165 2 : rangeKeyIters = append(rangeKeyIters, li)
1166 : }
1167 2 : return nil
1168 : }
1169 :
1170 2 : for i := range c.inputs {
1171 2 : // If the level is annotated with l0SublevelInfo, expand it into one
1172 2 : // level per sublevel.
1173 2 : // TODO(jackson): Perform this expansion even earlier when we pick the
1174 2 : // compaction?
1175 2 : if len(c.inputs[i].l0SublevelInfo) > 0 {
1176 2 : for _, info := range c.startLevel.l0SublevelInfo {
1177 2 : sublevelCompactionLevel := &compactionLevel{0, info.LevelSlice, nil}
1178 2 : if err := addItersForLevel(sublevelCompactionLevel, info.sublevel); err != nil {
1179 1 : return nil, nil, nil, err
1180 1 : }
1181 : }
1182 2 : continue
1183 : }
1184 2 : if err := addItersForLevel(&c.inputs[i], manifest.Level(c.inputs[i].level)); err != nil {
1185 1 : return nil, nil, nil, err
1186 1 : }
1187 : }
1188 : }
1189 :
1190 : // If there's only one constituent point iterator, we can avoid the overhead
1191 : // of a *mergingIter. This is possible, for example, when performing a flush
1192 : // of a single memtable. Otherwise, combine all the iterators into a merging
1193 : // iter.
1194 2 : pointIter = iters[0]
1195 2 : if len(iters) > 1 {
1196 2 : pointIter = newMergingIter(c.logger, &c.metrics.internalIterStats, cmp, nil, iters...)
1197 2 : }
1198 :
1199 : // In normal operation, levelIter iterates over the point operations in a
1200 : // level, and initializes a rangeDelIter pointer for the range deletions in
1201 : // each table. During compaction, we want to iterate over the merged view of
1202 : // point operations and range deletions. In order to do this we create one
1203 : // levelIter per level to iterate over the point operations, and collect up
1204 : // all the range deletion files.
1205 : //
1206 : // The range deletion levels are combined with a keyspanimpl.MergingIter. The
1207 : // resulting merged rangedel iterator is then included using an
1208 : // InterleavingIter.
1209 : // TODO(jackson): Consider using a defragmenting iterator to stitch together
1210 : // logical range deletions that were fragmented due to previous file
1211 : // boundaries.
1212 2 : if len(rangeDelIters) > 0 {
1213 2 : mi := &keyspanimpl.MergingIter{}
1214 2 : mi.Init(c.comparer, keyspan.NoopTransform, new(keyspanimpl.MergingBuffers), rangeDelIters...)
1215 2 : rangeDelIter = mi
1216 2 : }
1217 :
1218 : // If there are range key iterators, we need to combine them using
1219 : // keyspanimpl.MergingIter, and then interleave them among the points.
1220 2 : if len(rangeKeyIters) > 0 {
1221 2 : mi := &keyspanimpl.MergingIter{}
1222 2 : mi.Init(c.comparer, keyspan.NoopTransform, new(keyspanimpl.MergingBuffers), rangeKeyIters...)
1223 2 : // TODO(radu): why do we have a defragmenter here but not above?
1224 2 : di := &keyspan.DefragmentingIter{}
1225 2 : di.Init(c.comparer, mi, keyspan.DefragmentInternal, keyspan.StaticDefragmentReducer, new(keyspan.DefragmentingBuffers))
1226 2 : rangeKeyIter = di
1227 2 : }
1228 2 : return pointIter, rangeDelIter, rangeKeyIter, nil
1229 : }
1230 :
1231 : func (c *tableCompaction) newRangeDelIter(
1232 : ctx context.Context,
1233 : newIters tableNewIters,
1234 : f manifest.LevelFile,
1235 : opts IterOptions,
1236 : iiopts internalIterOpts,
1237 : l manifest.Layer,
1238 2 : ) (*noCloseIter, error) {
1239 2 : opts.layer = l
1240 2 : iterSet, err := newIters(ctx, f.TableMetadata, &opts, iiopts, iterRangeDeletions)
1241 2 : if err != nil {
1242 1 : return nil, err
1243 2 : } else if iterSet.rangeDeletion == nil {
1244 2 : // The file doesn't contain any range deletions.
1245 2 : return nil, nil
1246 2 : }
1247 : // Ensure that rangeDelIter is not closed until the compaction is
1248 : // finished. This is necessary because range tombstone processing
1249 : // requires the range tombstones to be held in memory for up to the
1250 : // lifetime of the compaction.
1251 2 : return &noCloseIter{iterSet.rangeDeletion}, nil
1252 : }
1253 :
1254 1 : func (c *tableCompaction) String() string {
1255 1 : if len(c.flush.flushables) != 0 {
1256 0 : return "flush\n"
1257 0 : }
1258 :
1259 1 : var buf bytes.Buffer
1260 1 : for level := c.startLevel.level; level <= c.outputLevel.level; level++ {
1261 1 : i := level - c.startLevel.level
1262 1 : fmt.Fprintf(&buf, "%d:", level)
1263 1 : for f := range c.inputs[i].files.All() {
1264 1 : fmt.Fprintf(&buf, " %s:%s-%s", f.TableNum, f.Smallest(), f.Largest())
1265 1 : }
1266 1 : fmt.Fprintf(&buf, "\n")
1267 : }
1268 1 : return buf.String()
1269 : }
1270 :
1271 : type manualCompaction struct {
1272 : // id is for internal bookkeeping.
1273 : id uint64
1274 : // Count of the retries due to concurrent compaction to overlapping levels.
1275 : retries int
1276 : level int
1277 : outputLevel int
1278 : done chan error
1279 : start []byte
1280 : end []byte
1281 : split bool
1282 : }
1283 :
1284 : type readCompaction struct {
1285 : level int
1286 : // [start, end] key ranges are used for de-duping.
1287 : start []byte
1288 : end []byte
1289 :
1290 : // The file associated with the compaction.
1291 : // If the file no longer belongs in the same
1292 : // level, then we skip the compaction.
1293 : tableNum base.TableNum
1294 : }
1295 :
1296 : // Removes compaction markers from files in a compaction. The rollback parameter
1297 : // indicates whether the compaction state should be rolled back to its original
1298 : // state in the case of an unsuccessful compaction.
1299 : //
1300 : // DB.mu must be held when calling this method, however this method can drop and
1301 : // re-acquire that mutex. All writes to the manifest for this compaction should
1302 : // have completed by this point.
1303 2 : func (d *DB) clearCompactingState(c *tableCompaction, rollback bool) {
1304 2 : c.versionEditApplied = true
1305 2 : for _, cl := range c.inputs {
1306 2 : for f := range cl.files.All() {
1307 2 : if !f.IsCompacting() {
1308 0 : d.opts.Logger.Fatalf("L%d->L%d: %s not being compacted", c.startLevel.level, c.outputLevel.level, f.TableNum)
1309 0 : }
1310 2 : if !rollback {
1311 2 : // On success all compactions other than move and delete-only compactions
1312 2 : // transition the file into the Compacted state. Move-compacted files
1313 2 : // become eligible for compaction again and transition back to NotCompacting.
1314 2 : // Delete-only compactions could, on rare occasion, leave files untouched
1315 2 : // (eg. if files have a loose bound), so we revert them all to NotCompacting
1316 2 : // just in case they need to be compacted again.
1317 2 : if c.kind != compactionKindMove && c.kind != compactionKindDeleteOnly {
1318 2 : f.SetCompactionState(manifest.CompactionStateCompacted)
1319 2 : } else {
1320 2 : f.SetCompactionState(manifest.CompactionStateNotCompacting)
1321 2 : }
1322 2 : } else {
1323 2 : // Else, on rollback, all input files unconditionally transition back to
1324 2 : // NotCompacting.
1325 2 : f.SetCompactionState(manifest.CompactionStateNotCompacting)
1326 2 : }
1327 2 : f.IsIntraL0Compacting = false
1328 : }
1329 : }
1330 2 : l0InProgress := inProgressL0Compactions(d.getInProgressCompactionInfoLocked(c))
1331 2 : func() {
1332 2 : // InitCompactingFileInfo requires that no other manifest writes be
1333 2 : // happening in parallel with it, i.e. we're not in the midst of installing
1334 2 : // another version. Otherwise, it's possible that we've created another
1335 2 : // L0Sublevels instance, but not added it to the versions list, causing
1336 2 : // all the indices in TableMetadata to be inaccurate. To ensure this,
1337 2 : // grab the manifest lock.
1338 2 : d.mu.versions.logLock()
1339 2 : // It is a bit peculiar that we are fiddling with th current version state
1340 2 : // in a separate critical section from when this version was installed.
1341 2 : // But this fiddling is necessary if the compaction failed. When the
1342 2 : // compaction succeeded, we've already done this in UpdateVersionLocked, so
1343 2 : // this seems redundant. Anyway, we clear the pickedCompactionCache since we
1344 2 : // may be able to pick a better compaction (though when this compaction
1345 2 : // succeeded we've also cleared the cache in UpdateVersionLocked).
1346 2 : defer d.mu.versions.logUnlockAndInvalidatePickedCompactionCache()
1347 2 : d.mu.versions.latest.l0Organizer.InitCompactingFileInfo(l0InProgress)
1348 2 : }()
1349 : }
1350 :
1351 2 : func (d *DB) calculateDiskAvailableBytes() uint64 {
1352 2 : space, err := d.opts.FS.GetDiskUsage(d.dirname)
1353 2 : if err != nil {
1354 2 : if !errors.Is(err, vfs.ErrUnsupported) {
1355 1 : d.opts.EventListener.BackgroundError(err)
1356 1 : }
1357 : // Return the last value we managed to obtain.
1358 2 : return d.diskAvailBytes.Load()
1359 : }
1360 :
1361 2 : d.lowDiskSpaceReporter.Report(space.AvailBytes, space.TotalBytes, d.opts.EventListener)
1362 2 : d.diskAvailBytes.Store(space.AvailBytes)
1363 2 : return space.AvailBytes
1364 : }
1365 :
1366 : // maybeScheduleFlush schedules a flush if necessary.
1367 : //
1368 : // d.mu must be held when calling this.
1369 2 : func (d *DB) maybeScheduleFlush() {
1370 2 : if d.mu.compact.flushing || d.closed.Load() != nil || d.opts.ReadOnly {
1371 2 : return
1372 2 : }
1373 2 : if len(d.mu.mem.queue) <= 1 {
1374 2 : return
1375 2 : }
1376 :
1377 2 : if !d.passedFlushThreshold() {
1378 2 : return
1379 2 : }
1380 :
1381 2 : d.mu.compact.flushing = true
1382 2 : go d.flush()
1383 : }
1384 :
1385 2 : func (d *DB) passedFlushThreshold() bool {
1386 2 : var n int
1387 2 : var size uint64
1388 2 : for ; n < len(d.mu.mem.queue)-1; n++ {
1389 2 : if !d.mu.mem.queue[n].readyForFlush() {
1390 2 : break
1391 : }
1392 2 : if d.mu.mem.queue[n].flushForced {
1393 2 : // A flush was forced. Pretend the memtable size is the configured
1394 2 : // size. See minFlushSize below.
1395 2 : size += d.opts.MemTableSize
1396 2 : } else {
1397 2 : size += d.mu.mem.queue[n].totalBytes()
1398 2 : }
1399 : }
1400 2 : if n == 0 {
1401 2 : // None of the immutable memtables are ready for flushing.
1402 2 : return false
1403 2 : }
1404 :
1405 : // Only flush once the sum of the queued memtable sizes exceeds half the
1406 : // configured memtable size. This prevents flushing of memtables at startup
1407 : // while we're undergoing the ramp period on the memtable size. See
1408 : // DB.newMemTable().
1409 2 : minFlushSize := d.opts.MemTableSize / 2
1410 2 : return size >= minFlushSize
1411 : }
1412 :
1413 2 : func (d *DB) maybeScheduleDelayedFlush(tbl *memTable, dur time.Duration) {
1414 2 : var mem *flushableEntry
1415 2 : for _, m := range d.mu.mem.queue {
1416 2 : if m.flushable == tbl {
1417 2 : mem = m
1418 2 : break
1419 : }
1420 : }
1421 2 : if mem == nil || mem.flushForced {
1422 2 : return
1423 2 : }
1424 2 : deadline := d.timeNow().Add(dur)
1425 2 : if !mem.delayedFlushForcedAt.IsZero() && deadline.After(mem.delayedFlushForcedAt) {
1426 2 : // Already scheduled to flush sooner than within `dur`.
1427 2 : return
1428 2 : }
1429 2 : mem.delayedFlushForcedAt = deadline
1430 2 : go func() {
1431 2 : timer := time.NewTimer(dur)
1432 2 : defer timer.Stop()
1433 2 :
1434 2 : select {
1435 2 : case <-d.closedCh:
1436 2 : return
1437 2 : case <-mem.flushed:
1438 2 : return
1439 2 : case <-timer.C:
1440 2 : d.commit.mu.Lock()
1441 2 : defer d.commit.mu.Unlock()
1442 2 : d.mu.Lock()
1443 2 : defer d.mu.Unlock()
1444 2 :
1445 2 : // NB: The timer may fire concurrently with a call to Close. If a
1446 2 : // Close call beat us to acquiring d.mu, d.closed holds ErrClosed,
1447 2 : // and it's too late to flush anything. Otherwise, the Close call
1448 2 : // will block on locking d.mu until we've finished scheduling the
1449 2 : // flush and set `d.mu.compact.flushing` to true. Close will wait
1450 2 : // for the current flush to complete.
1451 2 : if d.closed.Load() != nil {
1452 1 : return
1453 1 : }
1454 :
1455 2 : if d.mu.mem.mutable == tbl {
1456 2 : _ = d.makeRoomForWrite(nil)
1457 2 : } else {
1458 2 : mem.flushForced = true
1459 2 : }
1460 2 : d.maybeScheduleFlush()
1461 : }
1462 : }()
1463 : }
1464 :
1465 2 : func (d *DB) flush() {
1466 2 : pprof.Do(context.Background(), flushLabels, func(context.Context) {
1467 2 : flushingWorkStart := crtime.NowMono()
1468 2 : d.mu.Lock()
1469 2 : defer d.mu.Unlock()
1470 2 : idleDuration := flushingWorkStart.Sub(d.mu.compact.noOngoingFlushStartTime)
1471 2 : var bytesFlushed uint64
1472 2 : var err error
1473 2 : if bytesFlushed, err = d.flush1(); err != nil {
1474 1 : // TODO(peter): count consecutive flush errors and backoff.
1475 1 : d.opts.EventListener.BackgroundError(err)
1476 1 : }
1477 2 : d.mu.compact.flushing = false
1478 2 : d.mu.compact.noOngoingFlushStartTime = crtime.NowMono()
1479 2 : workDuration := d.mu.compact.noOngoingFlushStartTime.Sub(flushingWorkStart)
1480 2 : d.mu.compact.flushWriteThroughput.Bytes += int64(bytesFlushed)
1481 2 : d.mu.compact.flushWriteThroughput.WorkDuration += workDuration
1482 2 : d.mu.compact.flushWriteThroughput.IdleDuration += idleDuration
1483 2 : // More flush work may have arrived while we were flushing, so schedule
1484 2 : // another flush if needed.
1485 2 : d.maybeScheduleFlush()
1486 2 : // Let the CompactionScheduler know, so that it can react immediately to
1487 2 : // an increase in DB.GetAllowedWithoutPermission.
1488 2 : d.opts.Experimental.CompactionScheduler.UpdateGetAllowedWithoutPermission()
1489 2 : // The flush may have produced too many files in a level, so schedule a
1490 2 : // compaction if needed.
1491 2 : d.maybeScheduleCompaction()
1492 2 : d.mu.compact.cond.Broadcast()
1493 : })
1494 : }
1495 :
1496 : // runIngestFlush is used to generate a flush version edit for sstables which
1497 : // were ingested as flushables. Both DB.mu and the manifest lock must be held
1498 : // while runIngestFlush is called.
1499 2 : func (d *DB) runIngestFlush(c *tableCompaction) (*manifest.VersionEdit, error) {
1500 2 : if len(c.flush.flushables) != 1 {
1501 0 : panic("pebble: ingestedFlushable must be flushed one at a time.")
1502 : }
1503 :
1504 : // Finding the target level for ingestion must use the latest version
1505 : // after the logLock has been acquired.
1506 2 : version := d.mu.versions.currentVersion()
1507 2 :
1508 2 : baseLevel := d.mu.versions.picker.getBaseLevel()
1509 2 : ve := &manifest.VersionEdit{}
1510 2 : var ingestSplitFiles []ingestSplitFile
1511 2 : ingestFlushable := c.flush.flushables[0].flushable.(*ingestedFlushable)
1512 2 :
1513 2 : updateLevelMetricsOnExcise := func(m *manifest.TableMetadata, level int, added []manifest.NewTableEntry) {
1514 2 : levelMetrics := c.metrics.perLevel[level]
1515 2 : if levelMetrics == nil {
1516 2 : levelMetrics = &LevelMetrics{}
1517 2 : c.metrics.perLevel[level] = levelMetrics
1518 2 : }
1519 2 : levelMetrics.TablesCount--
1520 2 : levelMetrics.TablesSize -= int64(m.Size)
1521 2 : levelMetrics.EstimatedReferencesSize -= m.EstimatedReferenceSize()
1522 2 : for i := range added {
1523 2 : levelMetrics.TablesCount++
1524 2 : levelMetrics.TablesSize += int64(added[i].Meta.Size)
1525 2 : levelMetrics.EstimatedReferencesSize += added[i].Meta.EstimatedReferenceSize()
1526 2 : }
1527 : }
1528 :
1529 2 : suggestSplit := d.opts.Experimental.IngestSplit != nil && d.opts.Experimental.IngestSplit() &&
1530 2 : d.FormatMajorVersion() >= FormatVirtualSSTables
1531 2 :
1532 2 : if suggestSplit || ingestFlushable.exciseSpan.Valid() {
1533 2 : // We could add deleted files to ve.
1534 2 : ve.DeletedTables = make(map[manifest.DeletedTableEntry]*manifest.TableMetadata)
1535 2 : }
1536 :
1537 2 : ctx := context.Background()
1538 2 : overlapChecker := &overlapChecker{
1539 2 : comparer: d.opts.Comparer,
1540 2 : newIters: d.newIters,
1541 2 : opts: IterOptions{
1542 2 : logger: d.opts.Logger,
1543 2 : Category: categoryIngest,
1544 2 : },
1545 2 : v: version,
1546 2 : }
1547 2 : replacedTables := make(map[base.TableNum][]manifest.NewTableEntry)
1548 2 : for _, file := range ingestFlushable.files {
1549 2 : var fileToSplit *manifest.TableMetadata
1550 2 : var level int
1551 2 :
1552 2 : // This file fits perfectly within the excise span, so we can slot it at L6.
1553 2 : if ingestFlushable.exciseSpan.Valid() &&
1554 2 : ingestFlushable.exciseSpan.Contains(d.cmp, file.Smallest()) &&
1555 2 : ingestFlushable.exciseSpan.Contains(d.cmp, file.Largest()) {
1556 2 : level = 6
1557 2 : } else {
1558 2 : // TODO(radu): this can perform I/O; we should not do this while holding DB.mu.
1559 2 : lsmOverlap, err := overlapChecker.DetermineLSMOverlap(ctx, file.UserKeyBounds())
1560 2 : if err != nil {
1561 0 : return nil, err
1562 0 : }
1563 2 : level, fileToSplit, err = ingestTargetLevel(
1564 2 : ctx, d.cmp, lsmOverlap, baseLevel, d.mu.compact.inProgress, file, suggestSplit,
1565 2 : )
1566 2 : if err != nil {
1567 0 : return nil, err
1568 0 : }
1569 : }
1570 :
1571 : // Add the current flushableIngest file to the version.
1572 2 : ve.NewTables = append(ve.NewTables, manifest.NewTableEntry{Level: level, Meta: file})
1573 2 : if fileToSplit != nil {
1574 1 : ingestSplitFiles = append(ingestSplitFiles, ingestSplitFile{
1575 1 : ingestFile: file,
1576 1 : splitFile: fileToSplit,
1577 1 : level: level,
1578 1 : })
1579 1 : }
1580 2 : levelMetrics := c.metrics.perLevel.level(level)
1581 2 : levelMetrics.TableBytesIngested += file.Size
1582 2 : levelMetrics.TablesIngested++
1583 : }
1584 2 : if ingestFlushable.exciseSpan.Valid() {
1585 2 : exciseBounds := ingestFlushable.exciseSpan.UserKeyBounds()
1586 2 : // Iterate through all levels and find files that intersect with exciseSpan.
1587 2 : for layer, ls := range version.AllLevelsAndSublevels() {
1588 2 : for m := range ls.Overlaps(d.cmp, ingestFlushable.exciseSpan.UserKeyBounds()).All() {
1589 2 : leftTable, rightTable, err := d.exciseTable(context.TODO(), exciseBounds, m, layer.Level(), tightExciseBounds)
1590 2 : if err != nil {
1591 0 : return nil, err
1592 0 : }
1593 2 : newFiles := applyExciseToVersionEdit(ve, m, leftTable, rightTable, layer.Level())
1594 2 : replacedTables[m.TableNum] = newFiles
1595 2 : updateLevelMetricsOnExcise(m, layer.Level(), newFiles)
1596 : }
1597 : }
1598 : }
1599 :
1600 2 : if len(ingestSplitFiles) > 0 {
1601 1 : if err := d.ingestSplit(context.TODO(), ve, updateLevelMetricsOnExcise, ingestSplitFiles, replacedTables); err != nil {
1602 0 : return nil, err
1603 0 : }
1604 : }
1605 :
1606 2 : return ve, nil
1607 : }
1608 :
1609 : // flush runs a compaction that copies the immutable memtables from memory to
1610 : // disk.
1611 : //
1612 : // d.mu must be held when calling this, but the mutex may be dropped and
1613 : // re-acquired during the course of this method.
1614 2 : func (d *DB) flush1() (bytesFlushed uint64, err error) {
1615 2 : // NB: The flushable queue can contain flushables of type ingestedFlushable.
1616 2 : // The sstables in ingestedFlushable.files must be placed into the appropriate
1617 2 : // level in the lsm. Let's say the flushable queue contains a prefix of
1618 2 : // regular immutable memtables, then an ingestedFlushable, and then the
1619 2 : // mutable memtable. When the flush of the ingestedFlushable is performed,
1620 2 : // it needs an updated view of the lsm. That is, the prefix of immutable
1621 2 : // memtables must have already been flushed. Similarly, if there are two
1622 2 : // contiguous ingestedFlushables in the queue, then the first flushable must
1623 2 : // be flushed, so that the second flushable can see an updated view of the
1624 2 : // lsm.
1625 2 : //
1626 2 : // Given the above, we restrict flushes to either some prefix of regular
1627 2 : // memtables, or a single flushable of type ingestedFlushable. The DB.flush
1628 2 : // function will call DB.maybeScheduleFlush again, so a new flush to finish
1629 2 : // the remaining flush work should be scheduled right away.
1630 2 : //
1631 2 : // NB: Large batches placed in the flushable queue share the WAL with the
1632 2 : // previous memtable in the queue. We must ensure the property that both the
1633 2 : // large batch and the memtable with which it shares a WAL are flushed
1634 2 : // together. The property ensures that the minimum unflushed log number
1635 2 : // isn't incremented incorrectly. Since a flushableBatch.readyToFlush always
1636 2 : // returns true, and since the large batch will always be placed right after
1637 2 : // the memtable with which it shares a WAL, the property is naturally
1638 2 : // ensured. The large batch will always be placed after the memtable with
1639 2 : // which it shares a WAL because we ensure it in DB.commitWrite by holding
1640 2 : // the commitPipeline.mu and then holding DB.mu. As an extra defensive
1641 2 : // measure, if we try to flush the memtable without also flushing the
1642 2 : // flushable batch in the same flush, since the memtable and flushableBatch
1643 2 : // have the same logNum, the logNum invariant check below will trigger.
1644 2 : var n, inputs int
1645 2 : var inputBytes uint64
1646 2 : var ingest bool
1647 2 : for ; n < len(d.mu.mem.queue)-1; n++ {
1648 2 : if f, ok := d.mu.mem.queue[n].flushable.(*ingestedFlushable); ok {
1649 2 : if n == 0 {
1650 2 : // The first flushable is of type ingestedFlushable. Since these
1651 2 : // must be flushed individually, we perform a flush for just
1652 2 : // this.
1653 2 : if !f.readyForFlush() {
1654 0 : // This check is almost unnecessary, but we guard against it
1655 0 : // just in case this invariant changes in the future.
1656 0 : panic("pebble: ingestedFlushable should always be ready to flush.")
1657 : }
1658 : // By setting n = 1, we ensure that the first flushable(n == 0)
1659 : // is scheduled for a flush. The number of tables added is equal to the
1660 : // number of files in the ingest operation.
1661 2 : n = 1
1662 2 : inputs = len(f.files)
1663 2 : ingest = true
1664 2 : break
1665 2 : } else {
1666 2 : // There was some prefix of flushables which weren't of type
1667 2 : // ingestedFlushable. So, perform a flush for those.
1668 2 : break
1669 : }
1670 : }
1671 2 : if !d.mu.mem.queue[n].readyForFlush() {
1672 1 : break
1673 : }
1674 2 : inputBytes += d.mu.mem.queue[n].inuseBytes()
1675 : }
1676 2 : if n == 0 {
1677 0 : // None of the immutable memtables are ready for flushing.
1678 0 : return 0, nil
1679 0 : }
1680 2 : if !ingest {
1681 2 : // Flushes of memtables add the prefix of n memtables from the flushable
1682 2 : // queue.
1683 2 : inputs = n
1684 2 : }
1685 :
1686 : // Require that every memtable being flushed has a log number less than the
1687 : // new minimum unflushed log number.
1688 2 : minUnflushedLogNum := d.mu.mem.queue[n].logNum
1689 2 : if !d.opts.DisableWAL {
1690 2 : for i := 0; i < n; i++ {
1691 2 : if logNum := d.mu.mem.queue[i].logNum; logNum >= minUnflushedLogNum {
1692 0 : panic(errors.AssertionFailedf("logNum invariant violated: flushing %d items; %d:type=%T,logNum=%d; %d:type=%T,logNum=%d",
1693 0 : n,
1694 0 : i, d.mu.mem.queue[i].flushable, logNum,
1695 0 : n, d.mu.mem.queue[n].flushable, minUnflushedLogNum))
1696 : }
1697 : }
1698 : }
1699 :
1700 2 : c, err := newFlush(d.opts, d.mu.versions.currentVersion(), d.mu.versions.latest.l0Organizer,
1701 2 : d.mu.versions.picker.getBaseLevel(), d.mu.mem.queue[:n], d.timeNow(), d.TableFormat(), d.determineCompactionValueSeparation)
1702 2 : if err != nil {
1703 0 : return 0, err
1704 0 : }
1705 2 : c.AddInProgressLocked(d)
1706 2 :
1707 2 : jobID := d.newJobIDLocked()
1708 2 : info := FlushInfo{
1709 2 : JobID: int(jobID),
1710 2 : Input: inputs,
1711 2 : InputBytes: inputBytes,
1712 2 : Ingest: ingest,
1713 2 : }
1714 2 : d.opts.EventListener.FlushBegin(info)
1715 2 :
1716 2 : startTime := d.timeNow()
1717 2 :
1718 2 : var ve *manifest.VersionEdit
1719 2 : var stats compact.Stats
1720 2 : // To determine the target level of the files in the ingestedFlushable, we
1721 2 : // need to acquire the logLock, and not release it for that duration. Since
1722 2 : // UpdateVersionLocked acquires it anyway, we create the VersionEdit for
1723 2 : // ingestedFlushable outside runCompaction. For all other flush cases, we
1724 2 : // construct the VersionEdit inside runCompaction.
1725 2 : var compactionErr error
1726 2 : if c.kind != compactionKindIngestedFlushable {
1727 2 : ve, stats, compactionErr = d.runCompaction(jobID, c)
1728 2 : }
1729 :
1730 2 : err = d.mu.versions.UpdateVersionLocked(func() (versionUpdate, error) {
1731 2 : err := compactionErr
1732 2 : if c.kind == compactionKindIngestedFlushable {
1733 2 : ve, err = d.runIngestFlush(c)
1734 2 : }
1735 2 : info.Duration = d.timeNow().Sub(startTime)
1736 2 : if err != nil {
1737 1 : return versionUpdate{}, err
1738 1 : }
1739 :
1740 2 : validateVersionEdit(ve, d.opts.Comparer.ValidateKey, d.opts.Comparer.FormatKey, d.opts.Logger)
1741 2 : for i := range ve.NewTables {
1742 2 : e := &ve.NewTables[i]
1743 2 : info.Output = append(info.Output, e.Meta.TableInfo())
1744 2 : // Ingested tables are not necessarily flushed to L0. Record the level of
1745 2 : // each ingested file explicitly.
1746 2 : if ingest {
1747 2 : info.IngestLevels = append(info.IngestLevels, e.Level)
1748 2 : }
1749 : }
1750 :
1751 : // The flush succeeded or it produced an empty sstable. In either case we
1752 : // want to bump the minimum unflushed log number to the log number of the
1753 : // oldest unflushed memtable.
1754 2 : ve.MinUnflushedLogNum = minUnflushedLogNum
1755 2 : if c.kind != compactionKindIngestedFlushable {
1756 2 : l0Metrics := c.metrics.perLevel.level(0)
1757 2 : if d.opts.DisableWAL {
1758 2 : // If the WAL is disabled, every flushable has a zero [logSize],
1759 2 : // resulting in zero bytes in. Instead, use the number of bytes we
1760 2 : // flushed as the BytesIn. This ensures we get a reasonable w-amp
1761 2 : // calculation even when the WAL is disabled.
1762 2 : l0Metrics.TableBytesIn = l0Metrics.TableBytesFlushed + l0Metrics.BlobBytesFlushed
1763 2 : } else {
1764 2 : for i := 0; i < n; i++ {
1765 2 : l0Metrics.TableBytesIn += d.mu.mem.queue[i].logSize
1766 2 : }
1767 : }
1768 2 : } else {
1769 2 : // c.kind == compactionKindIngestedFlushable && we could have deleted files due
1770 2 : // to ingest-time splits or excises.
1771 2 : ingestFlushable := c.flush.flushables[0].flushable.(*ingestedFlushable)
1772 2 : exciseBounds := ingestFlushable.exciseSpan.UserKeyBounds()
1773 2 : for c2 := range d.mu.compact.inProgress {
1774 2 : // Check if this compaction overlaps with the excise span. Note that just
1775 2 : // checking if the inputs individually overlap with the excise span
1776 2 : // isn't sufficient; for instance, a compaction could have [a,b] and [e,f]
1777 2 : // as inputs and write it all out as [a,b,e,f] in one sstable. If we're
1778 2 : // doing a [c,d) excise at the same time as this compaction, we will have
1779 2 : // to error out the whole compaction as we can't guarantee it hasn't/won't
1780 2 : // write a file overlapping with the excise span.
1781 2 : bounds := c2.Bounds()
1782 2 : if bounds != nil && bounds.Overlaps(d.cmp, &exciseBounds) {
1783 2 : c2.Cancel()
1784 2 : }
1785 : }
1786 :
1787 2 : if len(ve.DeletedTables) > 0 {
1788 2 : // Iterate through all other compactions, and check if their inputs have
1789 2 : // been replaced due to an ingest-time split or excise. In that case,
1790 2 : // cancel the compaction.
1791 2 : for c2 := range d.mu.compact.inProgress {
1792 2 : for level, table := range c2.Tables() {
1793 2 : if _, ok := ve.DeletedTables[manifest.DeletedTableEntry{FileNum: table.TableNum, Level: level}]; ok {
1794 2 : c2.Cancel()
1795 2 : break
1796 : }
1797 : }
1798 : }
1799 : }
1800 : }
1801 2 : return versionUpdate{
1802 2 : VE: ve,
1803 2 : JobID: jobID,
1804 2 : Metrics: c.metrics.perLevel,
1805 2 : InProgressCompactionsFn: func() []compactionInfo { return d.getInProgressCompactionInfoLocked(c) },
1806 : }, nil
1807 : })
1808 :
1809 : // If err != nil, then the flush will be retried, and we will recalculate
1810 : // these metrics.
1811 2 : if err == nil {
1812 2 : d.mu.snapshots.cumulativePinnedCount += stats.CumulativePinnedKeys
1813 2 : d.mu.snapshots.cumulativePinnedSize += stats.CumulativePinnedSize
1814 2 : d.mu.versions.metrics.Keys.MissizedTombstonesCount += stats.CountMissizedDels
1815 2 : }
1816 :
1817 2 : d.clearCompactingState(c, err != nil)
1818 2 : delete(d.mu.compact.inProgress, c)
1819 2 : d.mu.versions.incrementCompactions(c.kind, c.extraLevels, c.metrics.picker,
1820 2 : c.metrics.bytesWritten.Load(), err)
1821 2 :
1822 2 : var flushed flushableList
1823 2 : if err == nil {
1824 2 : flushed = d.mu.mem.queue[:n]
1825 2 : d.mu.mem.queue = d.mu.mem.queue[n:]
1826 2 : d.updateReadStateLocked(d.opts.DebugCheck)
1827 2 : d.updateTableStatsLocked(ve.NewTables)
1828 2 : if ingest {
1829 2 : d.mu.versions.metrics.Flush.AsIngestCount++
1830 2 : for _, l := range c.metrics.perLevel {
1831 2 : if l != nil {
1832 2 : d.mu.versions.metrics.Flush.AsIngestBytes += l.TableBytesIngested
1833 2 : d.mu.versions.metrics.Flush.AsIngestTableCount += l.TablesIngested
1834 2 : }
1835 : }
1836 : }
1837 2 : d.maybeTransitionSnapshotsToFileOnlyLocked()
1838 : }
1839 : // Signal FlushEnd after installing the new readState. This helps for unit
1840 : // tests that use the callback to trigger a read using an iterator with
1841 : // IterOptions.OnlyReadGuaranteedDurable.
1842 2 : info.Err = err
1843 2 : if info.Err == nil && len(ve.NewTables) == 0 {
1844 2 : info.Err = errEmptyTable
1845 2 : }
1846 2 : info.Done = true
1847 2 : info.TotalDuration = d.timeNow().Sub(startTime)
1848 2 : d.opts.EventListener.FlushEnd(info)
1849 2 :
1850 2 : // The order of these operations matters here for ease of testing.
1851 2 : // Removing the reader reference first allows tests to be guaranteed that
1852 2 : // the memtable reservation has been released by the time a synchronous
1853 2 : // flush returns. readerUnrefLocked may also produce obsolete files so the
1854 2 : // call to deleteObsoleteFiles must happen after it.
1855 2 : for i := range flushed {
1856 2 : flushed[i].readerUnrefLocked(true)
1857 2 : }
1858 :
1859 2 : d.deleteObsoleteFiles(jobID)
1860 2 :
1861 2 : // Mark all the memtables we flushed as flushed.
1862 2 : for i := range flushed {
1863 2 : close(flushed[i].flushed)
1864 2 : }
1865 :
1866 2 : return inputBytes, err
1867 : }
1868 :
1869 : // maybeTransitionSnapshotsToFileOnlyLocked transitions any "eventually
1870 : // file-only" snapshots to be file-only if all their visible state has been
1871 : // flushed to sstables.
1872 : //
1873 : // REQUIRES: d.mu.
1874 2 : func (d *DB) maybeTransitionSnapshotsToFileOnlyLocked() {
1875 2 : earliestUnflushedSeqNum := d.getEarliestUnflushedSeqNumLocked()
1876 2 : currentVersion := d.mu.versions.currentVersion()
1877 2 : for s := d.mu.snapshots.root.next; s != &d.mu.snapshots.root; {
1878 2 : if s.efos == nil {
1879 2 : s = s.next
1880 2 : continue
1881 : }
1882 2 : overlapsFlushable := false
1883 2 : if base.Visible(earliestUnflushedSeqNum, s.efos.seqNum, base.SeqNumMax) {
1884 2 : // There are some unflushed keys that are still visible to the EFOS.
1885 2 : // Check if any memtables older than the EFOS contain keys within a
1886 2 : // protected range of the EFOS. If no, we can transition.
1887 2 : protectedRanges := make([]bounded, len(s.efos.protectedRanges))
1888 2 : for i := range s.efos.protectedRanges {
1889 2 : protectedRanges[i] = s.efos.protectedRanges[i]
1890 2 : }
1891 2 : for i := range d.mu.mem.queue {
1892 2 : if !base.Visible(d.mu.mem.queue[i].logSeqNum, s.efos.seqNum, base.SeqNumMax) {
1893 1 : // All keys in this memtable are newer than the EFOS. Skip this
1894 1 : // memtable.
1895 1 : continue
1896 : }
1897 : // NB: computePossibleOverlaps could have false positives, such as if
1898 : // the flushable is a flushable ingest and not a memtable. In that
1899 : // case we don't open the sstables to check; we just pessimistically
1900 : // assume an overlap.
1901 2 : d.mu.mem.queue[i].computePossibleOverlaps(func(b bounded) shouldContinue {
1902 2 : overlapsFlushable = true
1903 2 : return stopIteration
1904 2 : }, protectedRanges...)
1905 2 : if overlapsFlushable {
1906 2 : break
1907 : }
1908 : }
1909 : }
1910 2 : if overlapsFlushable {
1911 2 : s = s.next
1912 2 : continue
1913 : }
1914 2 : currentVersion.Ref()
1915 2 :
1916 2 : // NB: s.efos.transitionToFileOnlySnapshot could close s, in which
1917 2 : // case s.next would be nil. Save it before calling it.
1918 2 : next := s.next
1919 2 : _ = s.efos.transitionToFileOnlySnapshot(currentVersion)
1920 2 : s = next
1921 : }
1922 : }
1923 :
1924 : // maybeScheduleCompactionAsync should be used when
1925 : // we want to possibly schedule a compaction, but don't
1926 : // want to eat the cost of running maybeScheduleCompaction.
1927 : // This method should be launched in a separate goroutine.
1928 : // d.mu must not be held when this is called.
1929 0 : func (d *DB) maybeScheduleCompactionAsync() {
1930 0 : defer d.compactionSchedulers.Done()
1931 0 :
1932 0 : d.mu.Lock()
1933 0 : d.maybeScheduleCompaction()
1934 0 : d.mu.Unlock()
1935 0 : }
1936 :
1937 : // maybeScheduleCompaction schedules a compaction if necessary.
1938 : //
1939 : // WARNING: maybeScheduleCompaction and Schedule must be the only ways that
1940 : // any compactions are run. These ensure that the pickedCompactionCache is
1941 : // used and not stale (by ensuring invalidation is done).
1942 : //
1943 : // Even compactions that are not scheduled by the CompactionScheduler must be
1944 : // run using maybeScheduleCompaction, since starting those compactions needs
1945 : // to invalidate the pickedCompactionCache.
1946 : //
1947 : // Requires d.mu to be held.
1948 2 : func (d *DB) maybeScheduleCompaction() {
1949 2 : d.mu.versions.logLock()
1950 2 : defer d.mu.versions.logUnlock()
1951 2 : env := d.makeCompactionEnvLocked()
1952 2 : if env == nil {
1953 2 : return
1954 2 : }
1955 : // env.inProgressCompactions will become stale once we pick a compaction, so
1956 : // it needs to be kept fresh. Also, the pickedCompaction in the
1957 : // pickedCompactionCache is not valid if we pick a compaction before using
1958 : // it, since those earlier compactions can mark the same file as compacting.
1959 :
1960 : // Delete-only compactions are expected to be cheap and reduce future
1961 : // compaction work, so schedule them directly instead of using the
1962 : // CompactionScheduler.
1963 2 : if d.tryScheduleDeleteOnlyCompaction() {
1964 2 : env.inProgressCompactions = d.getInProgressCompactionInfoLocked(nil)
1965 2 : d.mu.versions.pickedCompactionCache.invalidate()
1966 2 : }
1967 : // Download compactions have their own concurrency and do not currently
1968 : // interact with CompactionScheduler.
1969 : //
1970 : // TODO(sumeer): integrate with CompactionScheduler, since these consume
1971 : // disk write bandwidth.
1972 2 : if d.tryScheduleDownloadCompactions(*env, d.opts.MaxConcurrentDownloads()) {
1973 2 : env.inProgressCompactions = d.getInProgressCompactionInfoLocked(nil)
1974 2 : d.mu.versions.pickedCompactionCache.invalidate()
1975 2 : }
1976 : // The remaining compactions are scheduled by the CompactionScheduler.
1977 2 : if d.mu.versions.pickedCompactionCache.isWaiting() {
1978 2 : // CompactionScheduler already knows that the DB is waiting to run a
1979 2 : // compaction.
1980 2 : return
1981 2 : }
1982 : // INVARIANT: !pickedCompactionCache.isWaiting. The following loop will
1983 : // either exit after successfully starting all the compactions it can pick,
1984 : // or will exit with one pickedCompaction in the cache, and isWaiting=true.
1985 2 : for {
1986 2 : // Do not have a pickedCompaction in the cache.
1987 2 : pc := d.pickAnyCompaction(*env)
1988 2 : if pc == nil {
1989 2 : return
1990 2 : }
1991 2 : success, grantHandle := d.opts.Experimental.CompactionScheduler.TrySchedule()
1992 2 : if !success {
1993 2 : // Can't run now, but remember this pickedCompaction in the cache.
1994 2 : d.mu.versions.pickedCompactionCache.add(pc)
1995 2 : return
1996 2 : }
1997 2 : d.runPickedCompaction(pc, grantHandle)
1998 2 : env.inProgressCompactions = d.getInProgressCompactionInfoLocked(nil)
1999 : }
2000 : }
2001 :
2002 : // makeCompactionEnv attempts to create a compactionEnv necessary during
2003 : // compaction picking. If the DB is closed or marked as read-only,
2004 : // makeCompactionEnv returns nil to indicate that compactions may not be
2005 : // performed. Else, a new compactionEnv is constructed using the current DB
2006 : // state.
2007 : //
2008 : // Compaction picking needs a coherent view of a Version. For example, we need
2009 : // to exclude concurrent ingestions from making a decision on which level to
2010 : // ingest into that conflicts with our compaction decision.
2011 : //
2012 : // A pickedCompaction constructed using a compactionEnv must only be used if
2013 : // the latest Version has not changed.
2014 : //
2015 : // REQUIRES: d.mu and d.mu.versions.logLock are held.
2016 2 : func (d *DB) makeCompactionEnvLocked() *compactionEnv {
2017 2 : if d.closed.Load() != nil || d.opts.ReadOnly {
2018 2 : return nil
2019 2 : }
2020 2 : env := &compactionEnv{
2021 2 : diskAvailBytes: d.diskAvailBytes.Load(),
2022 2 : earliestSnapshotSeqNum: d.mu.snapshots.earliest(),
2023 2 : earliestUnflushedSeqNum: d.getEarliestUnflushedSeqNumLocked(),
2024 2 : inProgressCompactions: d.getInProgressCompactionInfoLocked(nil),
2025 2 : readCompactionEnv: readCompactionEnv{
2026 2 : readCompactions: &d.mu.compact.readCompactions,
2027 2 : flushing: d.mu.compact.flushing || d.passedFlushThreshold(),
2028 2 : rescheduleReadCompaction: &d.mu.compact.rescheduleReadCompaction,
2029 2 : },
2030 2 : }
2031 2 : if !d.problemSpans.IsEmpty() {
2032 1 : env.problemSpans = &d.problemSpans
2033 1 : }
2034 2 : return env
2035 : }
2036 :
2037 : // pickAnyCompaction tries to pick a manual or automatic compaction.
2038 2 : func (d *DB) pickAnyCompaction(env compactionEnv) (pc pickedCompaction) {
2039 2 : // Pick a score-based compaction first, since a misshapen LSM is bad.
2040 2 : if !d.opts.DisableAutomaticCompactions {
2041 2 : if pc = d.mu.versions.picker.pickAutoScore(env); pc != nil {
2042 2 : return pc
2043 2 : }
2044 : }
2045 : // Pick a manual compaction, if any.
2046 2 : if pc = d.pickManualCompaction(env); pc != nil {
2047 2 : return pc
2048 2 : }
2049 2 : if !d.opts.DisableAutomaticCompactions {
2050 2 : return d.mu.versions.picker.pickAutoNonScore(env)
2051 2 : }
2052 2 : return nil
2053 : }
2054 :
2055 : // runPickedCompaction kicks off the provided pickedCompaction. In case the
2056 : // pickedCompaction is a manual compaction, the corresponding manualCompaction
2057 : // is removed from d.mu.compact.manual.
2058 : //
2059 : // REQUIRES: d.mu and d.mu.versions.logLock is held.
2060 2 : func (d *DB) runPickedCompaction(pc pickedCompaction, grantHandle CompactionGrantHandle) {
2061 2 : var doneChannel chan error
2062 2 : if pc.ManualID() > 0 {
2063 2 : for i := range d.mu.compact.manual {
2064 2 : if d.mu.compact.manual[i].id == pc.ManualID() {
2065 2 : doneChannel = d.mu.compact.manual[i].done
2066 2 : d.mu.compact.manual = slices.Delete(d.mu.compact.manual, i, i+1)
2067 2 : d.mu.compact.manualLen.Store(int32(len(d.mu.compact.manual)))
2068 2 : break
2069 : }
2070 : }
2071 2 : if doneChannel == nil {
2072 0 : panic(errors.AssertionFailedf("did not find manual compaction with id %d", pc.ManualID()))
2073 : }
2074 : }
2075 :
2076 2 : d.mu.compact.compactingCount++
2077 2 : c := pc.ConstructCompaction(d, grantHandle)
2078 2 : c.AddInProgressLocked(d)
2079 2 : go func() {
2080 2 : d.compact(c, doneChannel)
2081 2 : }()
2082 : }
2083 :
2084 : // Schedule implements DBForCompaction (it is called by the
2085 : // CompactionScheduler).
2086 2 : func (d *DB) Schedule(grantHandle CompactionGrantHandle) bool {
2087 2 : d.mu.Lock()
2088 2 : defer d.mu.Unlock()
2089 2 : d.mu.versions.logLock()
2090 2 : defer d.mu.versions.logUnlock()
2091 2 : isWaiting := d.mu.versions.pickedCompactionCache.isWaiting()
2092 2 : if !isWaiting {
2093 0 : return false
2094 0 : }
2095 2 : pc := d.mu.versions.pickedCompactionCache.getForRunning()
2096 2 : if pc == nil {
2097 2 : env := d.makeCompactionEnvLocked()
2098 2 : if env != nil {
2099 2 : pc = d.pickAnyCompaction(*env)
2100 2 : }
2101 2 : if pc == nil {
2102 0 : d.mu.versions.pickedCompactionCache.setNotWaiting()
2103 0 : return false
2104 0 : }
2105 : }
2106 : // INVARIANT: pc != nil and is not in the cache. isWaiting is true, since
2107 : // there may be more compactions to run.
2108 2 : d.runPickedCompaction(pc, grantHandle)
2109 2 : return true
2110 : }
2111 :
2112 : // GetWaitingCompaction implements DBForCompaction (it is called by the
2113 : // CompactionScheduler).
2114 2 : func (d *DB) GetWaitingCompaction() (bool, WaitingCompaction) {
2115 2 : d.mu.Lock()
2116 2 : defer d.mu.Unlock()
2117 2 : d.mu.versions.logLock()
2118 2 : defer d.mu.versions.logUnlock()
2119 2 : isWaiting := d.mu.versions.pickedCompactionCache.isWaiting()
2120 2 : if !isWaiting {
2121 2 : return false, WaitingCompaction{}
2122 2 : }
2123 2 : pc := d.mu.versions.pickedCompactionCache.peek()
2124 2 : if pc == nil {
2125 2 : // Need to pick a compaction.
2126 2 : env := d.makeCompactionEnvLocked()
2127 2 : if env != nil {
2128 2 : pc = d.pickAnyCompaction(*env)
2129 2 : }
2130 2 : if pc == nil {
2131 2 : // Call setNotWaiting so that next call to GetWaitingCompaction can
2132 2 : // return early.
2133 2 : d.mu.versions.pickedCompactionCache.setNotWaiting()
2134 2 : return false, WaitingCompaction{}
2135 2 : } else {
2136 2 : d.mu.versions.pickedCompactionCache.add(pc)
2137 2 : }
2138 : }
2139 : // INVARIANT: pc != nil and is in the cache.
2140 2 : return true, pc.WaitingCompaction()
2141 : }
2142 :
2143 : // GetAllowedWithoutPermission implements DBForCompaction (it is called by the
2144 : // CompactionScheduler).
2145 2 : func (d *DB) GetAllowedWithoutPermission() int {
2146 2 : allowedBasedOnBacklog := int(d.mu.versions.curCompactionConcurrency.Load())
2147 2 : allowedBasedOnManual := 0
2148 2 : manualBacklog := int(d.mu.compact.manualLen.Load())
2149 2 : if manualBacklog > 0 {
2150 2 : _, maxAllowed := d.opts.CompactionConcurrencyRange()
2151 2 : allowedBasedOnManual = min(maxAllowed, manualBacklog+allowedBasedOnBacklog)
2152 2 : }
2153 2 : return max(allowedBasedOnBacklog, allowedBasedOnManual)
2154 : }
2155 :
2156 : // tryScheduleDownloadCompactions tries to start download compactions.
2157 : //
2158 : // Requires d.mu to be held. Updates d.mu.compact.downloads.
2159 : //
2160 : // Returns true iff at least one compaction was started.
2161 2 : func (d *DB) tryScheduleDownloadCompactions(env compactionEnv, maxConcurrentDownloads int) bool {
2162 2 : started := false
2163 2 : vers := d.mu.versions.currentVersion()
2164 2 : for i := 0; i < len(d.mu.compact.downloads); {
2165 2 : if d.mu.compact.downloadingCount >= maxConcurrentDownloads {
2166 2 : break
2167 : }
2168 2 : download := d.mu.compact.downloads[i]
2169 2 : switch d.tryLaunchDownloadCompaction(download, vers, d.mu.versions.latest.l0Organizer, env, maxConcurrentDownloads) {
2170 2 : case launchedCompaction:
2171 2 : started = true
2172 2 : continue
2173 1 : case didNotLaunchCompaction:
2174 1 : // See if we can launch a compaction for another download task.
2175 1 : i++
2176 2 : case downloadTaskCompleted:
2177 2 : // Task is completed and must be removed.
2178 2 : d.mu.compact.downloads = slices.Delete(d.mu.compact.downloads, i, i+1)
2179 : }
2180 : }
2181 2 : return started
2182 : }
2183 :
2184 2 : func (d *DB) pickManualCompaction(env compactionEnv) (pc pickedCompaction) {
2185 2 : v := d.mu.versions.currentVersion()
2186 2 : for len(d.mu.compact.manual) > 0 {
2187 2 : manual := d.mu.compact.manual[0]
2188 2 : pc, retryLater := newPickedManualCompaction(v, d.mu.versions.latest.l0Organizer,
2189 2 : d.opts, env, d.mu.versions.picker.getBaseLevel(), manual)
2190 2 : if pc != nil {
2191 2 : return pc
2192 2 : }
2193 2 : if retryLater {
2194 2 : // We are not able to run this manual compaction at this time.
2195 2 : // Inability to run the head blocks later manual compactions.
2196 2 : manual.retries++
2197 2 : return nil
2198 2 : }
2199 : // Manual compaction is a no-op. Signal that it's complete.
2200 2 : manual.done <- nil
2201 2 : d.mu.compact.manual = d.mu.compact.manual[1:]
2202 2 : d.mu.compact.manualLen.Store(int32(len(d.mu.compact.manual)))
2203 : }
2204 2 : return nil
2205 : }
2206 :
2207 : // tryScheduleDeleteOnlyCompaction tries to kick off a delete-only compaction
2208 : // for all files that can be deleted as suggested by deletionHints.
2209 : //
2210 : // Requires d.mu to be held. Updates d.mu.compact.deletionHints.
2211 : //
2212 : // Returns true iff a compaction was started.
2213 2 : func (d *DB) tryScheduleDeleteOnlyCompaction() bool {
2214 2 : if d.opts.private.disableDeleteOnlyCompactions || d.opts.DisableAutomaticCompactions ||
2215 2 : len(d.mu.compact.deletionHints) == 0 {
2216 2 : return false
2217 2 : }
2218 2 : if _, maxConcurrency := d.opts.CompactionConcurrencyRange(); d.mu.compact.compactingCount >= maxConcurrency {
2219 2 : return false
2220 2 : }
2221 2 : v := d.mu.versions.currentVersion()
2222 2 : snapshots := d.mu.snapshots.toSlice()
2223 2 : // We need to save the value of exciseEnabled in the compaction itself, as
2224 2 : // it can change dynamically between now and when the compaction runs.
2225 2 : exciseEnabled := d.FormatMajorVersion() >= FormatVirtualSSTables &&
2226 2 : d.opts.Experimental.EnableDeleteOnlyCompactionExcises != nil && d.opts.Experimental.EnableDeleteOnlyCompactionExcises()
2227 2 : inputs, resolvedHints, unresolvedHints := checkDeleteCompactionHints(d.cmp, v, d.mu.compact.deletionHints, snapshots, exciseEnabled)
2228 2 : d.mu.compact.deletionHints = unresolvedHints
2229 2 :
2230 2 : if len(inputs) > 0 {
2231 2 : c := newDeleteOnlyCompaction(d.opts, v, inputs, d.timeNow(), resolvedHints, exciseEnabled)
2232 2 : d.mu.compact.compactingCount++
2233 2 : c.AddInProgressLocked(d)
2234 2 : go d.compact(c, nil)
2235 2 : return true
2236 2 : }
2237 2 : return false
2238 : }
2239 :
2240 : // deleteCompactionHintType indicates whether the deleteCompactionHint was
2241 : // generated from a span containing a range del (point key only), a range key
2242 : // delete (range key only), or both a point and range key.
2243 : type deleteCompactionHintType uint8
2244 :
2245 : const (
2246 : // NOTE: While these are primarily used as enumeration types, they are also
2247 : // used for some bitwise operations. Care should be taken when updating.
2248 : deleteCompactionHintTypeUnknown deleteCompactionHintType = iota
2249 : deleteCompactionHintTypePointKeyOnly
2250 : deleteCompactionHintTypeRangeKeyOnly
2251 : deleteCompactionHintTypePointAndRangeKey
2252 : )
2253 :
2254 : // String implements fmt.Stringer.
2255 1 : func (h deleteCompactionHintType) String() string {
2256 1 : switch h {
2257 0 : case deleteCompactionHintTypeUnknown:
2258 0 : return "unknown"
2259 1 : case deleteCompactionHintTypePointKeyOnly:
2260 1 : return "point-key-only"
2261 1 : case deleteCompactionHintTypeRangeKeyOnly:
2262 1 : return "range-key-only"
2263 1 : case deleteCompactionHintTypePointAndRangeKey:
2264 1 : return "point-and-range-key"
2265 0 : default:
2266 0 : panic(fmt.Sprintf("unknown hint type: %d", h))
2267 : }
2268 : }
2269 :
2270 : // compactionHintFromKeys returns a deleteCompactionHintType given a slice of
2271 : // keyspan.Keys.
2272 2 : func compactionHintFromKeys(keys []keyspan.Key) deleteCompactionHintType {
2273 2 : var hintType deleteCompactionHintType
2274 2 : for _, k := range keys {
2275 2 : switch k.Kind() {
2276 2 : case base.InternalKeyKindRangeDelete:
2277 2 : hintType |= deleteCompactionHintTypePointKeyOnly
2278 2 : case base.InternalKeyKindRangeKeyDelete:
2279 2 : hintType |= deleteCompactionHintTypeRangeKeyOnly
2280 0 : default:
2281 0 : panic(fmt.Sprintf("unsupported key kind: %s", k.Kind()))
2282 : }
2283 : }
2284 2 : return hintType
2285 : }
2286 :
2287 : // A deleteCompactionHint records a user key and sequence number span that has been
2288 : // deleted by a range tombstone. A hint is recorded if at least one sstable
2289 : // falls completely within both the user key and sequence number spans.
2290 : // Once the tombstones and the observed completely-contained sstables fall
2291 : // into the same snapshot stripe, a delete-only compaction may delete any
2292 : // sstables within the range.
2293 : type deleteCompactionHint struct {
2294 : // The type of key span that generated this hint (point key, range key, or
2295 : // both).
2296 : hintType deleteCompactionHintType
2297 : // start and end are user keys specifying a key range [start, end) of
2298 : // deleted keys.
2299 : start []byte
2300 : end []byte
2301 : // The level of the file containing the range tombstone(s) when the hint
2302 : // was created. Only lower levels need to be searched for files that may
2303 : // be deleted.
2304 : tombstoneLevel int
2305 : // The file containing the range tombstone(s) that created the hint.
2306 : tombstoneFile *manifest.TableMetadata
2307 : // The smallest and largest sequence numbers of the abutting tombstones
2308 : // merged to form this hint. All of a tables' keys must be less than the
2309 : // tombstone smallest sequence number to be deleted. All of a tables'
2310 : // sequence numbers must fall into the same snapshot stripe as the
2311 : // tombstone largest sequence number to be deleted.
2312 : tombstoneLargestSeqNum base.SeqNum
2313 : tombstoneSmallestSeqNum base.SeqNum
2314 : // The smallest sequence number of a sstable that was found to be covered
2315 : // by this hint. The hint cannot be resolved until this sequence number is
2316 : // in the same snapshot stripe as the largest tombstone sequence number.
2317 : // This is set when a hint is created, so the LSM may look different and
2318 : // notably no longer contain the sstable that contained the key at this
2319 : // sequence number.
2320 : fileSmallestSeqNum base.SeqNum
2321 : }
2322 :
2323 : type deletionHintOverlap int8
2324 :
2325 : const (
2326 : // hintDoesNotApply indicates that the hint does not apply to the file.
2327 : hintDoesNotApply deletionHintOverlap = iota
2328 : // hintExcisesFile indicates that the hint excises a portion of the file,
2329 : // and the format major version of the DB supports excises.
2330 : hintExcisesFile
2331 : // hintDeletesFile indicates that the hint deletes the entirety of the file.
2332 : hintDeletesFile
2333 : )
2334 :
2335 1 : func (h deleteCompactionHint) String() string {
2336 1 : return fmt.Sprintf(
2337 1 : "L%d.%s %s-%s seqnums(tombstone=%d-%d, file-smallest=%d, type=%s)",
2338 1 : h.tombstoneLevel, h.tombstoneFile.TableNum, h.start, h.end,
2339 1 : h.tombstoneSmallestSeqNum, h.tombstoneLargestSeqNum, h.fileSmallestSeqNum,
2340 1 : h.hintType,
2341 1 : )
2342 1 : }
2343 :
2344 : func (h *deleteCompactionHint) canDeleteOrExcise(
2345 : cmp Compare, m *manifest.TableMetadata, snapshots compact.Snapshots, exciseEnabled bool,
2346 2 : ) deletionHintOverlap {
2347 2 : // The file can only be deleted if all of its keys are older than the
2348 2 : // earliest tombstone aggregated into the hint. Note that we use
2349 2 : // m.LargestSeqNumAbsolute, not m.LargestSeqNum. Consider a compaction that
2350 2 : // zeroes sequence numbers. A compaction may zero the sequence number of a
2351 2 : // key with a sequence number > h.tombstoneSmallestSeqNum and set it to
2352 2 : // zero. If we looked at m.LargestSeqNum, the resulting output file would
2353 2 : // appear to not contain any keys more recent than the oldest tombstone. To
2354 2 : // avoid this error, the largest pre-zeroing sequence number is maintained
2355 2 : // in LargestSeqNumAbsolute and used here to make the determination whether
2356 2 : // the file's keys are older than all of the hint's tombstones.
2357 2 : if m.LargestSeqNumAbsolute >= h.tombstoneSmallestSeqNum || m.SmallestSeqNum < h.fileSmallestSeqNum {
2358 2 : return hintDoesNotApply
2359 2 : }
2360 :
2361 : // The file's oldest key must be in the same snapshot stripe as the
2362 : // newest tombstone. NB: We already checked the hint's sequence numbers,
2363 : // but this file's oldest sequence number might be lower than the hint's
2364 : // smallest sequence number despite the file falling within the key range
2365 : // if this file was constructed after the hint by a compaction.
2366 2 : if snapshots.Index(h.tombstoneLargestSeqNum) != snapshots.Index(m.SmallestSeqNum) {
2367 0 : return hintDoesNotApply
2368 0 : }
2369 :
2370 2 : switch h.hintType {
2371 2 : case deleteCompactionHintTypePointKeyOnly:
2372 2 : // A hint generated by a range del span cannot delete tables that contain
2373 2 : // range keys.
2374 2 : if m.HasRangeKeys {
2375 1 : return hintDoesNotApply
2376 1 : }
2377 2 : case deleteCompactionHintTypeRangeKeyOnly:
2378 2 : // A hint generated by a range key del span cannot delete tables that
2379 2 : // contain point keys.
2380 2 : if m.HasPointKeys {
2381 2 : return hintDoesNotApply
2382 2 : }
2383 2 : case deleteCompactionHintTypePointAndRangeKey:
2384 : // A hint from a span that contains both range dels *and* range keys can
2385 : // only be deleted if both bounds fall within the hint. The next check takes
2386 : // care of this.
2387 0 : default:
2388 0 : panic(fmt.Sprintf("pebble: unknown delete compaction hint type: %d", h.hintType))
2389 : }
2390 2 : if cmp(h.start, m.Smallest().UserKey) <= 0 &&
2391 2 : base.UserKeyExclusive(h.end).CompareUpperBounds(cmp, m.UserKeyBounds().End) >= 0 {
2392 2 : return hintDeletesFile
2393 2 : }
2394 2 : if !exciseEnabled {
2395 2 : // The file's keys must be completely contained within the hint range; excises
2396 2 : // aren't allowed.
2397 2 : return hintDoesNotApply
2398 2 : }
2399 : // Check for any overlap. In cases of partial overlap, we can excise the part of the file
2400 : // that overlaps with the deletion hint.
2401 2 : if cmp(h.end, m.Smallest().UserKey) > 0 &&
2402 2 : (m.UserKeyBounds().End.CompareUpperBounds(cmp, base.UserKeyInclusive(h.start)) >= 0) {
2403 2 : return hintExcisesFile
2404 2 : }
2405 2 : return hintDoesNotApply
2406 : }
2407 :
2408 : // checkDeleteCompactionHints checks the passed-in deleteCompactionHints for those that
2409 : // can be resolved and those that cannot. A hint is considered resolved when its largest
2410 : // tombstone sequence number and the smallest sequence number of covered files fall in
2411 : // the same snapshot stripe. No more than maxHintsPerDeleteOnlyCompaction will be resolved
2412 : // per method call. Resolved and unresolved hints are returned in separate return values.
2413 : // The files that the resolved hints apply to, are returned as compactionLevels.
2414 : func checkDeleteCompactionHints(
2415 : cmp Compare,
2416 : v *manifest.Version,
2417 : hints []deleteCompactionHint,
2418 : snapshots compact.Snapshots,
2419 : exciseEnabled bool,
2420 2 : ) (levels []compactionLevel, resolved, unresolved []deleteCompactionHint) {
2421 2 : var files map[*manifest.TableMetadata]bool
2422 2 : var byLevel [numLevels][]*manifest.TableMetadata
2423 2 :
2424 2 : // Delete-only compactions can be quadratic (O(mn)) in terms of runtime
2425 2 : // where m = number of files in the delete-only compaction and n = number
2426 2 : // of resolved hints. To prevent these from growing unbounded, we cap
2427 2 : // the number of hints we resolve for one delete-only compaction. This
2428 2 : // cap only applies if exciseEnabled == true.
2429 2 : const maxHintsPerDeleteOnlyCompaction = 10
2430 2 :
2431 2 : unresolvedHints := hints[:0]
2432 2 : // Lazily populate resolvedHints, similar to files above.
2433 2 : resolvedHints := make([]deleteCompactionHint, 0)
2434 2 : for _, h := range hints {
2435 2 : // Check each compaction hint to see if it's resolvable. Resolvable
2436 2 : // hints are removed and trigger a delete-only compaction if any files
2437 2 : // in the current LSM still meet their criteria. Unresolvable hints
2438 2 : // are saved and don't trigger a delete-only compaction.
2439 2 : //
2440 2 : // When a compaction hint is created, the sequence numbers of the
2441 2 : // range tombstones and the covered file with the oldest key are
2442 2 : // recorded. The largest tombstone sequence number and the smallest
2443 2 : // file sequence number must be in the same snapshot stripe for the
2444 2 : // hint to be resolved. The below graphic models a compaction hint
2445 2 : // covering the keyspace [b, r). The hint completely contains two
2446 2 : // files, 000002 and 000003. The file 000003 contains the lowest
2447 2 : // covered sequence number at #90. The tombstone b.RANGEDEL.230:h has
2448 2 : // the highest tombstone sequence number incorporated into the hint.
2449 2 : // The hint may be resolved only once the snapshots at #100, #180 and
2450 2 : // #210 are all closed. File 000001 is not included within the hint
2451 2 : // because it extends beyond the range tombstones in user key space.
2452 2 : //
2453 2 : // 250
2454 2 : //
2455 2 : // |-b...230:h-|
2456 2 : // _____________________________________________________ snapshot #210
2457 2 : // 200 |--h.RANGEDEL.200:r--|
2458 2 : //
2459 2 : // _____________________________________________________ snapshot #180
2460 2 : //
2461 2 : // 150 +--------+
2462 2 : // +---------+ | 000003 |
2463 2 : // | 000002 | | |
2464 2 : // +_________+ | |
2465 2 : // 100_____________________|________|___________________ snapshot #100
2466 2 : // +--------+
2467 2 : // _____________________________________________________ snapshot #70
2468 2 : // +---------------+
2469 2 : // 50 | 000001 |
2470 2 : // | |
2471 2 : // +---------------+
2472 2 : // ______________________________________________________________
2473 2 : // a b c d e f g h i j k l m n o p q r s t u v w x y z
2474 2 :
2475 2 : if snapshots.Index(h.tombstoneLargestSeqNum) != snapshots.Index(h.fileSmallestSeqNum) ||
2476 2 : (len(resolvedHints) >= maxHintsPerDeleteOnlyCompaction && exciseEnabled) {
2477 2 : // Cannot resolve yet.
2478 2 : unresolvedHints = append(unresolvedHints, h)
2479 2 : continue
2480 : }
2481 :
2482 : // The hint h will be resolved and dropped, if it either affects no files at all
2483 : // or if the number of files it creates (eg. through excision) is less than or
2484 : // equal to the number of files it deletes. First, determine how many files are
2485 : // affected by this hint.
2486 2 : filesDeletedByCurrentHint := 0
2487 2 : var filesDeletedByLevel [7][]*manifest.TableMetadata
2488 2 : for l := h.tombstoneLevel + 1; l < numLevels; l++ {
2489 2 : for m := range v.Overlaps(l, base.UserKeyBoundsEndExclusive(h.start, h.end)).All() {
2490 2 : doesHintApply := h.canDeleteOrExcise(cmp, m, snapshots, exciseEnabled)
2491 2 : if m.IsCompacting() || doesHintApply == hintDoesNotApply || files[m] {
2492 2 : continue
2493 : }
2494 2 : switch doesHintApply {
2495 2 : case hintDeletesFile:
2496 2 : filesDeletedByCurrentHint++
2497 2 : case hintExcisesFile:
2498 2 : // Account for the original file being deleted.
2499 2 : filesDeletedByCurrentHint++
2500 2 : // An excise could produce up to 2 new files. If the hint
2501 2 : // leaves a fragment of the file on the left, decrement
2502 2 : // the counter once. If the hint leaves a fragment of the
2503 2 : // file on the right, decrement the counter once.
2504 2 : if cmp(h.start, m.Smallest().UserKey) > 0 {
2505 2 : filesDeletedByCurrentHint--
2506 2 : }
2507 2 : if m.UserKeyBounds().End.IsUpperBoundFor(cmp, h.end) {
2508 2 : filesDeletedByCurrentHint--
2509 2 : }
2510 : }
2511 2 : filesDeletedByLevel[l] = append(filesDeletedByLevel[l], m)
2512 : }
2513 : }
2514 2 : if filesDeletedByCurrentHint < 0 {
2515 2 : // This hint does not delete a sufficient number of files to warrant
2516 2 : // a delete-only compaction at this stage. Drop it (ie. don't add it
2517 2 : // to either resolved or unresolved hints) so it doesn't stick around
2518 2 : // forever.
2519 2 : continue
2520 : }
2521 : // This hint will be resolved and dropped.
2522 2 : for l := h.tombstoneLevel + 1; l < numLevels; l++ {
2523 2 : byLevel[l] = append(byLevel[l], filesDeletedByLevel[l]...)
2524 2 : for _, m := range filesDeletedByLevel[l] {
2525 2 : if files == nil {
2526 2 : // Construct files lazily, assuming most calls will not
2527 2 : // produce delete-only compactions.
2528 2 : files = make(map[*manifest.TableMetadata]bool)
2529 2 : }
2530 2 : files[m] = true
2531 : }
2532 : }
2533 2 : resolvedHints = append(resolvedHints, h)
2534 : }
2535 :
2536 2 : var compactLevels []compactionLevel
2537 2 : for l, files := range byLevel {
2538 2 : if len(files) == 0 {
2539 2 : continue
2540 : }
2541 2 : compactLevels = append(compactLevels, compactionLevel{
2542 2 : level: l,
2543 2 : files: manifest.NewLevelSliceKeySorted(cmp, files),
2544 2 : })
2545 : }
2546 2 : return compactLevels, resolvedHints, unresolvedHints
2547 : }
2548 :
2549 : // compact runs one compaction and maybe schedules another call to compact.
2550 2 : func (d *DB) compact(c compaction, errChannel chan error) {
2551 2 : pprof.Do(context.Background(), c.PprofLabels(d.opts.Experimental.UserKeyCategories), func(context.Context) {
2552 2 : func() {
2553 2 : d.mu.Lock()
2554 2 : defer d.mu.Unlock()
2555 2 : jobID := d.newJobIDLocked()
2556 2 :
2557 2 : compactErr := c.Execute(jobID, d)
2558 2 :
2559 2 : d.deleteObsoleteFiles(jobID)
2560 2 : // We send on the error channel only after we've deleted
2561 2 : // obsolete files so that tests performing manual compactions
2562 2 : // block until the obsolete files are deleted, and the test
2563 2 : // observes the deletion.
2564 2 : if errChannel != nil {
2565 2 : errChannel <- compactErr
2566 2 : }
2567 2 : if compactErr != nil {
2568 2 : d.handleCompactFailure(c, compactErr)
2569 2 : }
2570 2 : if c.IsDownload() {
2571 2 : d.mu.compact.downloadingCount--
2572 2 : } else {
2573 2 : d.mu.compact.compactingCount--
2574 2 : }
2575 2 : delete(d.mu.compact.inProgress, c)
2576 2 : // Add this compaction's duration to the cumulative duration. NB: This
2577 2 : // must be atomic with the above removal of c from
2578 2 : // d.mu.compact.InProgress to ensure Metrics.Compact.Duration does not
2579 2 : // miss or double count a completing compaction's duration.
2580 2 : d.mu.compact.duration += d.timeNow().Sub(c.BeganAt())
2581 : }()
2582 : // Done must not be called while holding any lock that needs to be
2583 : // acquired by Schedule. Also, it must be called after new Version has
2584 : // been installed, and metadata related to compactingCount and inProgress
2585 : // compactions has been updated. This is because when we are running at
2586 : // the limit of permitted compactions, Done can cause the
2587 : // CompactionScheduler to schedule another compaction. Note that the only
2588 : // compactions that may be scheduled by Done are those integrated with the
2589 : // CompactionScheduler.
2590 2 : c.GrantHandle().Done()
2591 2 : // The previous compaction may have produced too many files in a level, so
2592 2 : // reschedule another compaction if needed.
2593 2 : //
2594 2 : // The preceding Done call will not necessarily cause a compaction to be
2595 2 : // scheduled, so we also need to call maybeScheduleCompaction. And
2596 2 : // maybeScheduleCompaction encompasses all compactions, and not only those
2597 2 : // scheduled via the CompactionScheduler.
2598 2 : func() {
2599 2 : d.mu.Lock()
2600 2 : defer d.mu.Unlock()
2601 2 : d.maybeScheduleCompaction()
2602 2 : d.mu.compact.cond.Broadcast()
2603 2 : }()
2604 : })
2605 : }
2606 :
2607 2 : func (d *DB) handleCompactFailure(c compaction, err error) {
2608 2 : if errors.Is(err, ErrCancelledCompaction) {
2609 2 : // ErrCancelledCompaction is expected during normal operation, so we don't
2610 2 : // want to report it as a background error.
2611 2 : d.opts.Logger.Infof("%v", err)
2612 2 : return
2613 2 : }
2614 1 : c.RecordError(&d.problemSpans, err)
2615 1 : // TODO(peter): count consecutive compaction errors and backoff.
2616 1 : d.opts.EventListener.BackgroundError(err)
2617 : }
2618 :
2619 : // cleanupVersionEdit cleans up any on-disk artifacts that were created
2620 : // for the application of a versionEdit that is no longer going to be applied.
2621 : //
2622 : // d.mu must be held when calling this method.
2623 2 : func (d *DB) cleanupVersionEdit(ve *manifest.VersionEdit) {
2624 2 : obsoleteFiles := manifest.ObsoleteFiles{
2625 2 : TableBackings: make([]*manifest.TableBacking, 0, len(ve.NewTables)),
2626 2 : BlobFiles: make([]*manifest.PhysicalBlobFile, 0, len(ve.NewBlobFiles)),
2627 2 : }
2628 2 : deletedTables := make(map[base.TableNum]struct{})
2629 2 : for key := range ve.DeletedTables {
2630 2 : deletedTables[key.FileNum] = struct{}{}
2631 2 : }
2632 2 : for i := range ve.NewBlobFiles {
2633 1 : obsoleteFiles.AddBlob(ve.NewBlobFiles[i].Physical)
2634 1 : d.mu.versions.zombieBlobs.Add(objectInfo{
2635 1 : fileInfo: fileInfo{
2636 1 : FileNum: ve.NewBlobFiles[i].Physical.FileNum,
2637 1 : FileSize: ve.NewBlobFiles[i].Physical.Size,
2638 1 : },
2639 1 : isLocal: objstorage.IsLocalBlobFile(d.objProvider, ve.NewBlobFiles[i].Physical.FileNum),
2640 1 : })
2641 1 : }
2642 2 : for i := range ve.NewTables {
2643 2 : if ve.NewTables[i].Meta.Virtual {
2644 1 : // We handle backing files separately.
2645 1 : continue
2646 : }
2647 2 : if _, ok := deletedTables[ve.NewTables[i].Meta.TableNum]; ok {
2648 1 : // This file is being moved in this ve to a different level.
2649 1 : // Don't mark it as obsolete.
2650 1 : continue
2651 : }
2652 2 : obsoleteFiles.AddBacking(ve.NewTables[i].Meta.PhysicalMeta().TableBacking)
2653 : }
2654 2 : for i := range ve.CreatedBackingTables {
2655 1 : if ve.CreatedBackingTables[i].IsUnused() {
2656 0 : obsoleteFiles.AddBacking(ve.CreatedBackingTables[i])
2657 0 : }
2658 : }
2659 2 : for _, of := range obsoleteFiles.TableBackings {
2660 2 : // Add this file to zombie tables as well, as the versionSet
2661 2 : // asserts on whether every obsolete file was at one point
2662 2 : // marked zombie.
2663 2 : d.mu.versions.zombieTables.Add(objectInfo{
2664 2 : fileInfo: fileInfo{
2665 2 : FileNum: of.DiskFileNum,
2666 2 : FileSize: of.Size,
2667 2 : },
2668 2 : isLocal: objstorage.IsLocalTable(d.objProvider, of.DiskFileNum),
2669 2 : })
2670 2 : }
2671 2 : d.mu.versions.addObsoleteLocked(obsoleteFiles)
2672 : }
2673 :
2674 : // compact1 runs one compaction.
2675 : //
2676 : // d.mu must be held when calling this, but the mutex may be dropped and
2677 : // re-acquired during the course of this method.
2678 2 : func (d *DB) compact1(jobID JobID, c *tableCompaction) (err error) {
2679 2 : info := c.makeInfo(jobID)
2680 2 : d.opts.EventListener.CompactionBegin(info)
2681 2 : startTime := d.timeNow()
2682 2 :
2683 2 : ve, stats, err := d.runCompaction(jobID, c)
2684 2 :
2685 2 : info.Duration = d.timeNow().Sub(startTime)
2686 2 : if err == nil {
2687 2 : validateVersionEdit(ve, d.opts.Comparer.ValidateKey, d.opts.Comparer.FormatKey, d.opts.Logger)
2688 2 : err = d.mu.versions.UpdateVersionLocked(func() (versionUpdate, error) {
2689 2 : // Check if this compaction had a conflicting operation (eg. a d.excise())
2690 2 : // that necessitates it restarting from scratch. Note that since we hold
2691 2 : // the manifest lock, we don't expect this bool to change its value
2692 2 : // as only the holder of the manifest lock will ever write to it.
2693 2 : if c.cancel.Load() {
2694 2 : err = firstError(err, ErrCancelledCompaction)
2695 2 : // This is the first time we've seen a cancellation during the
2696 2 : // life of this compaction (or the original condition on err == nil
2697 2 : // would not have been true). We should delete any tables already
2698 2 : // created, as d.runCompaction did not do that.
2699 2 : d.cleanupVersionEdit(ve)
2700 2 : // Note that UpdateVersionLocked invalidates the pickedCompactionCache
2701 2 : // when we return, which is relevant because this failed compaction
2702 2 : // may be the highest priority to run next.
2703 2 : return versionUpdate{}, err
2704 2 : }
2705 2 : return versionUpdate{
2706 2 : VE: ve,
2707 2 : JobID: jobID,
2708 2 : Metrics: c.metrics.perLevel,
2709 2 : InProgressCompactionsFn: func() []compactionInfo { return d.getInProgressCompactionInfoLocked(c) },
2710 : }, nil
2711 : })
2712 : }
2713 :
2714 2 : info.Done = true
2715 2 : info.Err = err
2716 2 : if err == nil {
2717 2 : for i := range ve.NewTables {
2718 2 : e := &ve.NewTables[i]
2719 2 : info.Output.Tables = append(info.Output.Tables, e.Meta.TableInfo())
2720 2 : }
2721 2 : d.mu.snapshots.cumulativePinnedCount += stats.CumulativePinnedKeys
2722 2 : d.mu.snapshots.cumulativePinnedSize += stats.CumulativePinnedSize
2723 2 : d.mu.versions.metrics.Keys.MissizedTombstonesCount += stats.CountMissizedDels
2724 : }
2725 :
2726 : // NB: clearing compacting state must occur before updating the read state;
2727 : // L0Sublevels initialization depends on it.
2728 2 : d.clearCompactingState(c, err != nil)
2729 2 : d.mu.versions.incrementCompactions(c.kind, c.extraLevels, c.metrics.picker,
2730 2 : c.metrics.bytesWritten.Load(), err)
2731 2 : d.mu.versions.incrementCompactionBytes(-c.metrics.bytesWritten.Load())
2732 2 :
2733 2 : info.TotalDuration = d.timeNow().Sub(c.metrics.beganAt)
2734 2 : d.opts.EventListener.CompactionEnd(info)
2735 2 :
2736 2 : // Update the read state before deleting obsolete files because the
2737 2 : // read-state update will cause the previous version to be unref'd and if
2738 2 : // there are no references obsolete tables will be added to the obsolete
2739 2 : // table list.
2740 2 : if err == nil {
2741 2 : d.updateReadStateLocked(d.opts.DebugCheck)
2742 2 : d.updateTableStatsLocked(ve.NewTables)
2743 2 : }
2744 :
2745 2 : return err
2746 : }
2747 :
2748 : // runCopyCompaction runs a copy compaction where a new TableNum is created that
2749 : // is a byte-for-byte copy of the input file or span thereof in some cases. This
2750 : // is used in lieu of a move compaction when a file is being moved across the
2751 : // local/remote storage boundary. It could also be used in lieu of a rewrite
2752 : // compaction as part of a Download() call, which allows copying only a span of
2753 : // the external file, provided the file does not contain range keys or value
2754 : // blocks (see sstable.CopySpan).
2755 : //
2756 : // d.mu must be held when calling this method. The mutex will be released when
2757 : // doing IO.
2758 : func (d *DB) runCopyCompaction(
2759 : jobID JobID, c *tableCompaction,
2760 2 : ) (ve *manifest.VersionEdit, stats compact.Stats, _ error) {
2761 2 : if c.cancel.Load() {
2762 0 : return nil, compact.Stats{}, ErrCancelledCompaction
2763 0 : }
2764 2 : iter := c.startLevel.files.Iter()
2765 2 : inputMeta := iter.First()
2766 2 : if iter.Next() != nil {
2767 0 : return nil, compact.Stats{}, base.AssertionFailedf("got more than one file for a move compaction")
2768 0 : }
2769 2 : if inputMeta.BlobReferenceDepth > 0 || len(inputMeta.BlobReferences) > 0 {
2770 0 : return nil, compact.Stats{}, base.AssertionFailedf(
2771 0 : "copy compaction for %s with blob references (depth=%d, refs=%d)",
2772 0 : inputMeta.TableNum, inputMeta.BlobReferenceDepth, len(inputMeta.BlobReferences),
2773 0 : )
2774 0 : }
2775 2 : ve = &manifest.VersionEdit{
2776 2 : DeletedTables: map[manifest.DeletedTableEntry]*manifest.TableMetadata{
2777 2 : {Level: c.startLevel.level, FileNum: inputMeta.TableNum}: inputMeta,
2778 2 : },
2779 2 : }
2780 2 :
2781 2 : objMeta, err := d.objProvider.Lookup(base.FileTypeTable, inputMeta.TableBacking.DiskFileNum)
2782 2 : if err != nil {
2783 0 : return nil, compact.Stats{}, err
2784 0 : }
2785 : // This code does not support copying a shared table (which should never be necessary).
2786 2 : if objMeta.IsShared() {
2787 0 : return nil, compact.Stats{}, base.AssertionFailedf("copy compaction of shared table")
2788 0 : }
2789 :
2790 : // We are in the relatively more complex case where we need to copy this
2791 : // file to remote storage. Drop the db mutex while we do the copy
2792 : //
2793 : // To ease up cleanup of the local file and tracking of refs, we create
2794 : // a new FileNum. This has the potential of making the block cache less
2795 : // effective, however.
2796 2 : newMeta := &manifest.TableMetadata{
2797 2 : Size: inputMeta.Size,
2798 2 : CreationTime: inputMeta.CreationTime,
2799 2 : SmallestSeqNum: inputMeta.SmallestSeqNum,
2800 2 : LargestSeqNum: inputMeta.LargestSeqNum,
2801 2 : LargestSeqNumAbsolute: inputMeta.LargestSeqNumAbsolute,
2802 2 : Stats: inputMeta.Stats,
2803 2 : Virtual: inputMeta.Virtual,
2804 2 : SyntheticPrefixAndSuffix: inputMeta.SyntheticPrefixAndSuffix,
2805 2 : }
2806 2 : if inputMeta.HasPointKeys {
2807 2 : newMeta.ExtendPointKeyBounds(c.comparer.Compare,
2808 2 : inputMeta.PointKeyBounds.Smallest(),
2809 2 : inputMeta.PointKeyBounds.Largest())
2810 2 : }
2811 2 : if inputMeta.HasRangeKeys {
2812 2 : newMeta.ExtendRangeKeyBounds(c.comparer.Compare,
2813 2 : inputMeta.RangeKeyBounds.Smallest(),
2814 2 : inputMeta.RangeKeyBounds.Largest())
2815 2 : }
2816 2 : newMeta.TableNum = d.mu.versions.getNextTableNum()
2817 2 : if objMeta.IsExternal() {
2818 2 : // external -> local/shared copy. File must be virtual.
2819 2 : // We will update this size later after we produce the new backing file.
2820 2 : newMeta.InitVirtualBacking(base.DiskFileNum(newMeta.TableNum), inputMeta.TableBacking.Size)
2821 2 : } else {
2822 2 : // local -> shared copy. New file is guaranteed to not be virtual.
2823 2 : newMeta.InitPhysicalBacking()
2824 2 : }
2825 :
2826 : // NB: The order here is reversed, lock after unlock. This is similar to
2827 : // runCompaction.
2828 2 : d.mu.Unlock()
2829 2 : defer d.mu.Lock()
2830 2 :
2831 2 : deleteOnExit := false
2832 2 : defer func() {
2833 2 : if deleteOnExit {
2834 1 : _ = d.objProvider.Remove(base.FileTypeTable, newMeta.TableBacking.DiskFileNum)
2835 1 : }
2836 : }()
2837 :
2838 : // If the src obj is external, we're doing an external to local/shared copy.
2839 2 : if objMeta.IsExternal() {
2840 2 : ctx := context.TODO()
2841 2 : src, err := d.objProvider.OpenForReading(
2842 2 : ctx, base.FileTypeTable, inputMeta.TableBacking.DiskFileNum, objstorage.OpenOptions{},
2843 2 : )
2844 2 : if err != nil {
2845 0 : return nil, compact.Stats{}, err
2846 0 : }
2847 2 : defer func() {
2848 2 : if src != nil {
2849 0 : _ = src.Close()
2850 0 : }
2851 : }()
2852 :
2853 2 : w, _, err := d.objProvider.Create(
2854 2 : ctx, base.FileTypeTable, newMeta.TableBacking.DiskFileNum,
2855 2 : objstorage.CreateOptions{
2856 2 : PreferSharedStorage: d.shouldCreateShared(c.outputLevel.level),
2857 2 : },
2858 2 : )
2859 2 : if err != nil {
2860 0 : return nil, compact.Stats{}, err
2861 0 : }
2862 2 : deleteOnExit = true
2863 2 :
2864 2 : start, end := newMeta.Smallest(), newMeta.Largest()
2865 2 : if newMeta.SyntheticPrefixAndSuffix.HasPrefix() {
2866 2 : syntheticPrefix := newMeta.SyntheticPrefixAndSuffix.Prefix()
2867 2 : start.UserKey = syntheticPrefix.Invert(start.UserKey)
2868 2 : end.UserKey = syntheticPrefix.Invert(end.UserKey)
2869 2 : }
2870 2 : if newMeta.SyntheticPrefixAndSuffix.HasSuffix() {
2871 1 : // Extend the bounds as necessary so that the keys don't include suffixes.
2872 1 : start.UserKey = start.UserKey[:c.comparer.Split(start.UserKey)]
2873 1 : if n := c.comparer.Split(end.UserKey); n < len(end.UserKey) {
2874 0 : end = base.MakeRangeDeleteSentinelKey(c.comparer.ImmediateSuccessor(nil, end.UserKey[:n]))
2875 0 : }
2876 : }
2877 :
2878 : // NB: external files are always virtual.
2879 2 : var wrote uint64
2880 2 : err = d.fileCache.withReader(ctx, block.NoReadEnv, inputMeta.VirtualMeta(), func(r *sstable.Reader, env sstable.ReadEnv) error {
2881 2 : var err error
2882 2 : // TODO(radu): plumb a ReadEnv to CopySpan (it could use the buffer pool
2883 2 : // or update category stats).
2884 2 : wrote, err = sstable.CopySpan(ctx,
2885 2 : src, r, d.opts.MakeReaderOptions(),
2886 2 : w, d.opts.MakeWriterOptions(c.outputLevel.level, d.TableFormat()),
2887 2 : start, end,
2888 2 : )
2889 2 : return err
2890 2 : })
2891 :
2892 2 : src = nil // We passed src to CopySpan; it's responsible for closing it.
2893 2 : if err != nil {
2894 1 : if errors.Is(err, sstable.ErrEmptySpan) {
2895 1 : // The virtual table was empty. Just remove the backing file.
2896 1 : // Note that deleteOnExit is true so we will delete the created object.
2897 1 : outputMetrics := c.metrics.perLevel.level(c.outputLevel.level)
2898 1 : outputMetrics.TableBytesIn = inputMeta.Size
2899 1 :
2900 1 : return ve, compact.Stats{}, nil
2901 1 : }
2902 0 : return nil, compact.Stats{}, err
2903 : }
2904 2 : newMeta.TableBacking.Size = wrote
2905 2 : newMeta.Size = wrote
2906 2 : } else {
2907 2 : _, err := d.objProvider.LinkOrCopyFromLocal(context.TODO(), d.opts.FS,
2908 2 : d.objProvider.Path(objMeta), base.FileTypeTable, newMeta.TableBacking.DiskFileNum,
2909 2 : objstorage.CreateOptions{PreferSharedStorage: true})
2910 2 : if err != nil {
2911 0 : return nil, compact.Stats{}, err
2912 0 : }
2913 2 : deleteOnExit = true
2914 : }
2915 2 : ve.NewTables = []manifest.NewTableEntry{{
2916 2 : Level: c.outputLevel.level,
2917 2 : Meta: newMeta,
2918 2 : }}
2919 2 : if newMeta.Virtual {
2920 2 : ve.CreatedBackingTables = []*manifest.TableBacking{newMeta.TableBacking}
2921 2 : }
2922 2 : outputMetrics := c.metrics.perLevel.level(c.outputLevel.level)
2923 2 : outputMetrics.TableBytesIn = inputMeta.Size
2924 2 : outputMetrics.TableBytesCompacted = newMeta.Size
2925 2 : outputMetrics.TablesCompacted = 1
2926 2 :
2927 2 : if err := d.objProvider.Sync(); err != nil {
2928 0 : return nil, compact.Stats{}, err
2929 0 : }
2930 2 : deleteOnExit = false
2931 2 : return ve, compact.Stats{}, nil
2932 : }
2933 :
2934 : // applyHintOnFile applies a deleteCompactionHint to a file, and updates the
2935 : // versionEdit accordingly. It returns a list of new files that were created
2936 : // if the hint was applied partially to a file (eg. through an exciseTable as opposed
2937 : // to an outright deletion). levelMetrics is kept up-to-date with the number
2938 : // of tables deleted or excised.
2939 : func (d *DB) applyHintOnFile(
2940 : h deleteCompactionHint,
2941 : f *manifest.TableMetadata,
2942 : level int,
2943 : levelMetrics *LevelMetrics,
2944 : ve *manifest.VersionEdit,
2945 : hintOverlap deletionHintOverlap,
2946 2 : ) (newFiles []manifest.NewTableEntry, err error) {
2947 2 : if hintOverlap == hintDoesNotApply {
2948 0 : return nil, nil
2949 0 : }
2950 :
2951 : // The hint overlaps with at least part of the file.
2952 2 : if hintOverlap == hintDeletesFile {
2953 2 : // The hint deletes the entirety of this file.
2954 2 : ve.DeletedTables[manifest.DeletedTableEntry{
2955 2 : Level: level,
2956 2 : FileNum: f.TableNum,
2957 2 : }] = f
2958 2 : levelMetrics.TablesDeleted++
2959 2 : return nil, nil
2960 2 : }
2961 : // The hint overlaps with only a part of the file, not the entirety of it. We need
2962 : // to use d.exciseTable. (hintOverlap == hintExcisesFile)
2963 2 : if d.FormatMajorVersion() < FormatVirtualSSTables {
2964 0 : panic("pebble: delete-only compaction hint excising a file is not supported in this version")
2965 : }
2966 :
2967 2 : levelMetrics.TablesExcised++
2968 2 : exciseBounds := base.UserKeyBoundsEndExclusive(h.start, h.end)
2969 2 : leftTable, rightTable, err := d.exciseTable(context.TODO(), exciseBounds, f, level, tightExciseBounds)
2970 2 : if err != nil {
2971 0 : return nil, errors.Wrap(err, "error when running excise for delete-only compaction")
2972 0 : }
2973 2 : newFiles = applyExciseToVersionEdit(ve, f, leftTable, rightTable, level)
2974 2 : return newFiles, nil
2975 : }
2976 :
2977 : func (d *DB) runDeleteOnlyCompactionForLevel(
2978 : cl compactionLevel,
2979 : levelMetrics *LevelMetrics,
2980 : ve *manifest.VersionEdit,
2981 : snapshots compact.Snapshots,
2982 : fragments []deleteCompactionHintFragment,
2983 : exciseEnabled bool,
2984 2 : ) error {
2985 2 : if cl.level == 0 {
2986 0 : panic("cannot run delete-only compaction for L0")
2987 : }
2988 2 : curFragment := 0
2989 2 :
2990 2 : // Outer loop loops on files. Middle loop loops on fragments. Inner loop
2991 2 : // loops on raw fragments of hints. Number of fragments are bounded by
2992 2 : // the number of hints this compaction was created with, which is capped
2993 2 : // in the compaction picker to avoid very CPU-hot loops here.
2994 2 : for f := range cl.files.All() {
2995 2 : // curFile usually matches f, except if f got excised in which case
2996 2 : // it maps to a virtual file that replaces f, or nil if f got removed
2997 2 : // in its entirety.
2998 2 : curFile := f
2999 2 : for curFragment < len(fragments) && d.cmp(fragments[curFragment].start, f.Smallest().UserKey) <= 0 {
3000 2 : curFragment++
3001 2 : }
3002 2 : if curFragment > 0 {
3003 2 : curFragment--
3004 2 : }
3005 :
3006 2 : for ; curFragment < len(fragments); curFragment++ {
3007 2 : if f.UserKeyBounds().End.CompareUpperBounds(d.cmp, base.UserKeyInclusive(fragments[curFragment].start)) < 0 {
3008 2 : break
3009 : }
3010 : // Process all overlapping hints with this file. Note that applying
3011 : // a hint twice is idempotent; curFile should have already been excised
3012 : // the first time, resulting in no change the second time.
3013 2 : for _, h := range fragments[curFragment].hints {
3014 2 : if h.tombstoneLevel >= cl.level {
3015 2 : // We cannot excise out the deletion tombstone itself, or anything
3016 2 : // above it.
3017 2 : continue
3018 : }
3019 2 : hintOverlap := h.canDeleteOrExcise(d.cmp, curFile, snapshots, exciseEnabled)
3020 2 : if hintOverlap == hintDoesNotApply {
3021 2 : continue
3022 : }
3023 2 : newFiles, err := d.applyHintOnFile(h, curFile, cl.level, levelMetrics, ve, hintOverlap)
3024 2 : if err != nil {
3025 0 : return err
3026 0 : }
3027 2 : if _, ok := ve.DeletedTables[manifest.DeletedTableEntry{Level: cl.level, FileNum: curFile.TableNum}]; ok {
3028 2 : curFile = nil
3029 2 : }
3030 2 : if len(newFiles) > 0 {
3031 2 : curFile = newFiles[len(newFiles)-1].Meta
3032 2 : } else if curFile == nil {
3033 2 : // Nothing remains of the file.
3034 2 : break
3035 : }
3036 : }
3037 2 : if curFile == nil {
3038 2 : // Nothing remains of the file.
3039 2 : break
3040 : }
3041 : }
3042 2 : if _, ok := ve.DeletedTables[manifest.DeletedTableEntry{
3043 2 : Level: cl.level,
3044 2 : FileNum: f.TableNum,
3045 2 : }]; !ok {
3046 0 : panic("pebble: delete-only compaction scheduled with hints that did not delete or excise a file")
3047 : }
3048 : }
3049 2 : return nil
3050 : }
3051 :
3052 : // deleteCompactionHintFragment represents a fragment of the key space and
3053 : // contains a set of deleteCompactionHints that apply to that fragment; a
3054 : // fragment starts at the start field and ends where the next fragment starts.
3055 : type deleteCompactionHintFragment struct {
3056 : start []byte
3057 : hints []deleteCompactionHint
3058 : }
3059 :
3060 : // Delete compaction hints can overlap with each other, and multiple fragments
3061 : // can apply to a single file. This function takes a list of hints and fragments
3062 : // them, to make it easier to apply them to non-overlapping files occupying a level;
3063 : // that way, files and hint fragments can be iterated on in lockstep, while efficiently
3064 : // being able to apply all hints overlapping with a given file.
3065 : func fragmentDeleteCompactionHints(
3066 : cmp Compare, hints []deleteCompactionHint,
3067 2 : ) []deleteCompactionHintFragment {
3068 2 : fragments := make([]deleteCompactionHintFragment, 0, len(hints)*2)
3069 2 : for i := range hints {
3070 2 : fragments = append(fragments, deleteCompactionHintFragment{start: hints[i].start},
3071 2 : deleteCompactionHintFragment{start: hints[i].end})
3072 2 : }
3073 2 : slices.SortFunc(fragments, func(i, j deleteCompactionHintFragment) int {
3074 2 : return cmp(i.start, j.start)
3075 2 : })
3076 2 : fragments = slices.CompactFunc(fragments, func(i, j deleteCompactionHintFragment) bool {
3077 2 : return bytes.Equal(i.start, j.start)
3078 2 : })
3079 2 : for _, h := range hints {
3080 2 : startIdx := sort.Search(len(fragments), func(i int) bool {
3081 2 : return cmp(fragments[i].start, h.start) >= 0
3082 2 : })
3083 2 : endIdx := sort.Search(len(fragments), func(i int) bool {
3084 2 : return cmp(fragments[i].start, h.end) >= 0
3085 2 : })
3086 2 : for i := startIdx; i < endIdx; i++ {
3087 2 : fragments[i].hints = append(fragments[i].hints, h)
3088 2 : }
3089 : }
3090 2 : return fragments
3091 : }
3092 :
3093 : // Runs a delete-only compaction.
3094 : //
3095 : // d.mu must *not* be held when calling this.
3096 : func (d *DB) runDeleteOnlyCompaction(
3097 : jobID JobID, c *tableCompaction, snapshots compact.Snapshots,
3098 2 : ) (ve *manifest.VersionEdit, stats compact.Stats, retErr error) {
3099 2 : fragments := fragmentDeleteCompactionHints(d.cmp, c.deleteOnly.hints)
3100 2 : ve = &manifest.VersionEdit{
3101 2 : DeletedTables: map[manifest.DeletedTableEntry]*manifest.TableMetadata{},
3102 2 : }
3103 2 : for _, cl := range c.inputs {
3104 2 : levelMetrics := c.metrics.perLevel.level(cl.level)
3105 2 : err := d.runDeleteOnlyCompactionForLevel(cl, levelMetrics, ve, snapshots, fragments, c.deleteOnly.exciseEnabled)
3106 2 : if err != nil {
3107 0 : return nil, stats, err
3108 0 : }
3109 : }
3110 : // Remove any files that were added and deleted in the same versionEdit.
3111 2 : ve.NewTables = slices.DeleteFunc(ve.NewTables, func(e manifest.NewTableEntry) bool {
3112 2 : entry := manifest.DeletedTableEntry{Level: e.Level, FileNum: e.Meta.TableNum}
3113 2 : if _, deleted := ve.DeletedTables[entry]; deleted {
3114 2 : delete(ve.DeletedTables, entry)
3115 2 : return true
3116 2 : }
3117 2 : return false
3118 : })
3119 : // Remove any entries from CreatedBackingTables that are not used in any
3120 : // NewFiles.
3121 2 : usedBackingFiles := make(map[base.DiskFileNum]struct{})
3122 2 : for _, e := range ve.NewTables {
3123 2 : if e.Meta.Virtual {
3124 2 : usedBackingFiles[e.Meta.TableBacking.DiskFileNum] = struct{}{}
3125 2 : }
3126 : }
3127 2 : ve.CreatedBackingTables = slices.DeleteFunc(ve.CreatedBackingTables, func(b *manifest.TableBacking) bool {
3128 2 : _, used := usedBackingFiles[b.DiskFileNum]
3129 2 : return !used
3130 2 : })
3131 : // Refresh the disk available statistic whenever a compaction/flush
3132 : // completes, before re-acquiring the mutex.
3133 2 : d.calculateDiskAvailableBytes()
3134 2 : return ve, stats, nil
3135 : }
3136 :
3137 : func (d *DB) runMoveCompaction(
3138 : jobID JobID, c *tableCompaction,
3139 2 : ) (ve *manifest.VersionEdit, stats compact.Stats, _ error) {
3140 2 : iter := c.startLevel.files.Iter()
3141 2 : meta := iter.First()
3142 2 : if iter.Next() != nil {
3143 0 : return nil, stats, base.AssertionFailedf("got more than one file for a move compaction")
3144 0 : }
3145 2 : if c.cancel.Load() {
3146 0 : return ve, stats, ErrCancelledCompaction
3147 0 : }
3148 2 : outputMetrics := c.metrics.perLevel.level(c.outputLevel.level)
3149 2 : outputMetrics.TableBytesMoved = meta.Size
3150 2 : outputMetrics.TablesMoved = 1
3151 2 : ve = &manifest.VersionEdit{
3152 2 : DeletedTables: map[manifest.DeletedTableEntry]*manifest.TableMetadata{
3153 2 : {Level: c.startLevel.level, FileNum: meta.TableNum}: meta,
3154 2 : },
3155 2 : NewTables: []manifest.NewTableEntry{
3156 2 : {Level: c.outputLevel.level, Meta: meta},
3157 2 : },
3158 2 : }
3159 2 :
3160 2 : return ve, stats, nil
3161 : }
3162 :
3163 : // runCompaction runs a compaction that produces new on-disk tables from
3164 : // memtables or old on-disk tables.
3165 : //
3166 : // runCompaction cannot be used for compactionKindIngestedFlushable.
3167 : //
3168 : // d.mu must be held when calling this, but the mutex may be dropped and
3169 : // re-acquired during the course of this method.
3170 : func (d *DB) runCompaction(
3171 : jobID JobID, c *tableCompaction,
3172 2 : ) (ve *manifest.VersionEdit, stats compact.Stats, retErr error) {
3173 2 : if c.cancel.Load() {
3174 2 : return ve, stats, ErrCancelledCompaction
3175 2 : }
3176 2 : switch c.kind {
3177 2 : case compactionKindDeleteOnly:
3178 2 : // Release the d.mu lock while doing I/O.
3179 2 : // Note the unusual order: Unlock and then Lock.
3180 2 : snapshots := d.mu.snapshots.toSlice()
3181 2 : d.mu.Unlock()
3182 2 : defer d.mu.Lock()
3183 2 : return d.runDeleteOnlyCompaction(jobID, c, snapshots)
3184 2 : case compactionKindMove:
3185 2 : return d.runMoveCompaction(jobID, c)
3186 2 : case compactionKindCopy:
3187 2 : return d.runCopyCompaction(jobID, c)
3188 0 : case compactionKindIngestedFlushable:
3189 0 : panic("pebble: runCompaction cannot handle compactionKindIngestedFlushable.")
3190 : }
3191 :
3192 2 : snapshots := d.mu.snapshots.toSlice()
3193 2 :
3194 2 : // Release the d.mu lock while doing I/O.
3195 2 : // Note the unusual order: Unlock and then Lock.
3196 2 : d.mu.Unlock()
3197 2 : defer d.mu.Lock()
3198 2 :
3199 2 : // Determine whether we should separate values into blob files.
3200 2 : //
3201 2 : // TODO(jackson): Currently we never separate values in non-tests. Choose
3202 2 : // and initialize the appropriate ValueSeparation implementation based on
3203 2 : // Options and the compaction inputs.
3204 2 : valueSeparation := c.getValueSeparation(jobID, c, c.tableFormat)
3205 2 :
3206 2 : result := d.compactAndWrite(jobID, c, snapshots, c.tableFormat, valueSeparation)
3207 2 : if result.Err == nil {
3208 2 : ve, result.Err = c.makeVersionEdit(result)
3209 2 : }
3210 2 : if result.Err != nil {
3211 2 : // Delete any created tables or blob files.
3212 2 : obsoleteFiles := manifest.ObsoleteFiles{
3213 2 : TableBackings: make([]*manifest.TableBacking, 0, len(result.Tables)),
3214 2 : BlobFiles: make([]*manifest.PhysicalBlobFile, 0, len(result.Blobs)),
3215 2 : }
3216 2 : d.mu.Lock()
3217 2 : for i := range result.Tables {
3218 1 : backing := &manifest.TableBacking{
3219 1 : DiskFileNum: result.Tables[i].ObjMeta.DiskFileNum,
3220 1 : Size: result.Tables[i].WriterMeta.Size,
3221 1 : }
3222 1 : obsoleteFiles.AddBacking(backing)
3223 1 : // Add this file to zombie tables as well, as the versionSet
3224 1 : // asserts on whether every obsolete file was at one point
3225 1 : // marked zombie.
3226 1 : d.mu.versions.zombieTables.AddMetadata(&result.Tables[i].ObjMeta, backing.Size)
3227 1 : }
3228 2 : for i := range result.Blobs {
3229 0 : obsoleteFiles.AddBlob(result.Blobs[i].Metadata)
3230 0 : // Add this file to zombie blobs as well, as the versionSet
3231 0 : // asserts on whether every obsolete file was at one point
3232 0 : // marked zombie.
3233 0 : d.mu.versions.zombieBlobs.AddMetadata(&result.Blobs[i].ObjMeta, result.Blobs[i].Metadata.Size)
3234 0 : }
3235 2 : d.mu.versions.addObsoleteLocked(obsoleteFiles)
3236 2 : d.mu.Unlock()
3237 : }
3238 : // Refresh the disk available statistic whenever a compaction/flush
3239 : // completes, before re-acquiring the mutex.
3240 2 : d.calculateDiskAvailableBytes()
3241 2 : return ve, result.Stats, result.Err
3242 : }
3243 :
3244 : // compactAndWrite runs the data part of a compaction, where we set up a
3245 : // compaction iterator and use it to write output tables.
3246 : func (d *DB) compactAndWrite(
3247 : jobID JobID,
3248 : c *tableCompaction,
3249 : snapshots compact.Snapshots,
3250 : tableFormat sstable.TableFormat,
3251 : valueSeparation compact.ValueSeparation,
3252 2 : ) (result compact.Result) {
3253 2 : // Compactions use a pool of buffers to read blocks, avoiding polluting the
3254 2 : // block cache with blocks that will not be read again. We initialize the
3255 2 : // buffer pool with a size 12. This initial size does not need to be
3256 2 : // accurate, because the pool will grow to accommodate the maximum number of
3257 2 : // blocks allocated at a given time over the course of the compaction. But
3258 2 : // choosing a size larger than that working set avoids any additional
3259 2 : // allocations to grow the size of the pool over the course of iteration.
3260 2 : //
3261 2 : // Justification for initial size 12: In a two-level compaction, at any
3262 2 : // given moment we'll have 2 index blocks in-use and 2 data blocks in-use.
3263 2 : // Additionally, when decoding a compressed block, we'll temporarily
3264 2 : // allocate 1 additional block to hold the compressed buffer. In the worst
3265 2 : // case that all input sstables have two-level index blocks (+2), value
3266 2 : // blocks (+2), range deletion blocks (+n) and range key blocks (+n), we'll
3267 2 : // additionally require 2n+4 blocks where n is the number of input sstables.
3268 2 : // Range deletion and range key blocks are relatively rare, and the cost of
3269 2 : // an additional allocation or two over the course of the compaction is
3270 2 : // considered to be okay. A larger initial size would cause the pool to hold
3271 2 : // on to more memory, even when it's not in-use because the pool will
3272 2 : // recycle buffers up to the current capacity of the pool. The memory use of
3273 2 : // a 12-buffer pool is expected to be within reason, even if all the buffers
3274 2 : // grow to the typical size of an index block (256 KiB) which would
3275 2 : // translate to 3 MiB per compaction.
3276 2 : c.iterationState.bufferPool.Init(12)
3277 2 : defer c.iterationState.bufferPool.Release()
3278 2 : blockReadEnv := block.ReadEnv{
3279 2 : BufferPool: &c.iterationState.bufferPool,
3280 2 : Stats: &c.metrics.internalIterStats,
3281 2 : IterStats: d.fileCache.SSTStatsCollector().Accumulator(
3282 2 : uint64(uintptr(unsafe.Pointer(c))),
3283 2 : categoryCompaction,
3284 2 : ),
3285 2 : }
3286 2 : if c.version != nil {
3287 2 : c.iterationState.valueFetcher.Init(&c.version.BlobFiles, d.fileCache, blockReadEnv)
3288 2 : }
3289 2 : iiopts := internalIterOpts{
3290 2 : compaction: true,
3291 2 : readEnv: sstable.ReadEnv{Block: blockReadEnv},
3292 2 : blobValueFetcher: &c.iterationState.valueFetcher,
3293 2 : }
3294 2 : defer func() { _ = c.iterationState.valueFetcher.Close() }()
3295 :
3296 2 : pointIter, rangeDelIter, rangeKeyIter, err := c.newInputIters(d.newIters, iiopts)
3297 2 : defer func() {
3298 2 : for _, closer := range c.iterationState.keyspanIterClosers {
3299 2 : closer.FragmentIterator.Close()
3300 2 : }
3301 : }()
3302 2 : if err != nil {
3303 1 : return compact.Result{Err: err}
3304 1 : }
3305 2 : cfg := compact.IterConfig{
3306 2 : Comparer: c.comparer,
3307 2 : Merge: d.merge,
3308 2 : TombstoneElision: c.delElision,
3309 2 : RangeKeyElision: c.rangeKeyElision,
3310 2 : Snapshots: snapshots,
3311 2 : AllowZeroSeqNum: c.allowZeroSeqNum(),
3312 2 : IneffectualSingleDeleteCallback: func(userKey []byte) {
3313 2 : d.opts.EventListener.PossibleAPIMisuse(PossibleAPIMisuseInfo{
3314 2 : Kind: IneffectualSingleDelete,
3315 2 : UserKey: slices.Clone(userKey),
3316 2 : })
3317 2 : },
3318 0 : NondeterministicSingleDeleteCallback: func(userKey []byte) {
3319 0 : d.opts.EventListener.PossibleAPIMisuse(PossibleAPIMisuseInfo{
3320 0 : Kind: NondeterministicSingleDelete,
3321 0 : UserKey: slices.Clone(userKey),
3322 0 : })
3323 0 : },
3324 2 : MissizedDeleteCallback: func(userKey []byte, elidedSize, expectedSize uint64) {
3325 2 : d.opts.EventListener.PossibleAPIMisuse(PossibleAPIMisuseInfo{
3326 2 : Kind: MissizedDelete,
3327 2 : UserKey: slices.Clone(userKey),
3328 2 : ExtraInfo: redact.Sprintf("elidedSize=%d,expectedSize=%d",
3329 2 : redact.SafeUint(elidedSize), redact.SafeUint(expectedSize)),
3330 2 : })
3331 2 : },
3332 : }
3333 2 : iter := compact.NewIter(cfg, pointIter, rangeDelIter, rangeKeyIter)
3334 2 :
3335 2 : runnerCfg := compact.RunnerConfig{
3336 2 : CompactionBounds: c.bounds,
3337 2 : L0SplitKeys: c.flush.l0Limits,
3338 2 : Grandparents: c.grandparents,
3339 2 : MaxGrandparentOverlapBytes: c.maxOverlapBytes,
3340 2 : TargetOutputFileSize: c.maxOutputFileSize,
3341 2 : GrantHandle: c.grantHandle,
3342 2 : }
3343 2 : runner := compact.NewRunner(runnerCfg, iter)
3344 2 :
3345 2 : var spanPolicyValid bool
3346 2 : var spanPolicy SpanPolicy
3347 2 : // If spanPolicyValid is true and spanPolicyEndKey is empty, then spanPolicy
3348 2 : // applies for the rest of the keyspace.
3349 2 : var spanPolicyEndKey []byte
3350 2 :
3351 2 : for runner.MoreDataToWrite() {
3352 2 : if c.cancel.Load() {
3353 2 : return runner.Finish().WithError(ErrCancelledCompaction)
3354 2 : }
3355 : // Create a new table.
3356 2 : firstKey := runner.FirstKey()
3357 2 : if !spanPolicyValid || (len(spanPolicyEndKey) > 0 && d.cmp(firstKey, spanPolicyEndKey) >= 0) {
3358 2 : var err error
3359 2 : spanPolicy, spanPolicyEndKey, err = d.opts.Experimental.SpanPolicyFunc(firstKey)
3360 2 : if err != nil {
3361 0 : return runner.Finish().WithError(err)
3362 0 : }
3363 2 : spanPolicyValid = true
3364 : }
3365 :
3366 2 : writerOpts := d.opts.MakeWriterOptions(c.outputLevel.level, tableFormat)
3367 2 : if spanPolicy.DisableValueSeparationBySuffix {
3368 1 : writerOpts.DisableValueBlocks = true
3369 1 : }
3370 2 : if spanPolicy.PreferFastCompression && writerOpts.Compression != block.NoCompression {
3371 0 : writerOpts.Compression = block.FastestCompression
3372 0 : }
3373 2 : vSep := valueSeparation
3374 2 : if spanPolicy.ValueStoragePolicy == ValueStorageLowReadLatency {
3375 1 : vSep = compact.NeverSeparateValues{}
3376 1 : }
3377 2 : objMeta, tw, err := d.newCompactionOutputTable(jobID, c, writerOpts)
3378 2 : if err != nil {
3379 1 : return runner.Finish().WithError(err)
3380 1 : }
3381 2 : runner.WriteTable(objMeta, tw, spanPolicyEndKey, vSep)
3382 : }
3383 2 : result = runner.Finish()
3384 2 : if result.Err == nil {
3385 2 : result.Err = d.objProvider.Sync()
3386 2 : }
3387 2 : return result
3388 : }
3389 :
3390 : // makeVersionEdit creates the version edit for a compaction, based on the
3391 : // tables in compact.Result.
3392 2 : func (c *tableCompaction) makeVersionEdit(result compact.Result) (*manifest.VersionEdit, error) {
3393 2 : ve := &manifest.VersionEdit{
3394 2 : DeletedTables: map[manifest.DeletedTableEntry]*manifest.TableMetadata{},
3395 2 : }
3396 2 : for _, cl := range c.inputs {
3397 2 : for f := range cl.files.All() {
3398 2 : ve.DeletedTables[manifest.DeletedTableEntry{
3399 2 : Level: cl.level,
3400 2 : FileNum: f.TableNum,
3401 2 : }] = f
3402 2 : }
3403 : }
3404 : // Add any newly constructed blob files to the version edit.
3405 2 : ve.NewBlobFiles = make([]manifest.BlobFileMetadata, len(result.Blobs))
3406 2 : for i := range result.Blobs {
3407 2 : ve.NewBlobFiles[i] = manifest.BlobFileMetadata{
3408 2 : FileID: base.BlobFileID(result.Blobs[i].Metadata.FileNum),
3409 2 : Physical: result.Blobs[i].Metadata,
3410 2 : }
3411 2 : }
3412 :
3413 2 : startLevelBytes := c.startLevel.files.TableSizeSum()
3414 2 :
3415 2 : outputMetrics := c.metrics.perLevel.level(c.outputLevel.level)
3416 2 : outputMetrics.TableBytesIn = startLevelBytes
3417 2 : // TODO(jackson): This BytesRead value does not include any blob files
3418 2 : // written. It either should, or we should add a separate metric.
3419 2 : outputMetrics.TableBytesRead = c.outputLevel.files.TableSizeSum()
3420 2 : outputMetrics.BlobBytesCompacted = result.Stats.CumulativeBlobFileSize
3421 2 : if c.flush.flushables != nil {
3422 2 : outputMetrics.BlobBytesFlushed = result.Stats.CumulativeBlobFileSize
3423 2 : }
3424 2 : if len(c.extraLevels) > 0 {
3425 2 : outputMetrics.TableBytesIn += c.extraLevels[0].files.TableSizeSum()
3426 2 : }
3427 2 : outputMetrics.TableBytesRead += outputMetrics.TableBytesIn
3428 2 :
3429 2 : if len(c.flush.flushables) == 0 {
3430 2 : c.metrics.perLevel.level(c.startLevel.level)
3431 2 : }
3432 2 : if len(c.extraLevels) > 0 {
3433 2 : c.metrics.perLevel.level(c.extraLevels[0].level)
3434 2 : outputMetrics.MultiLevel.TableBytesInTop = startLevelBytes
3435 2 : outputMetrics.MultiLevel.TableBytesIn = outputMetrics.TableBytesIn
3436 2 : outputMetrics.MultiLevel.TableBytesRead = outputMetrics.TableBytesRead
3437 2 : }
3438 :
3439 2 : inputLargestSeqNumAbsolute := c.inputLargestSeqNumAbsolute()
3440 2 : ve.NewTables = make([]manifest.NewTableEntry, len(result.Tables))
3441 2 : for i := range result.Tables {
3442 2 : t := &result.Tables[i]
3443 2 :
3444 2 : if t.WriterMeta.Properties.NumValuesInBlobFiles > 0 {
3445 2 : if len(t.BlobReferences) == 0 {
3446 0 : return nil, base.AssertionFailedf("num values in blob files %d but no blob references",
3447 0 : t.WriterMeta.Properties.NumValuesInBlobFiles)
3448 0 : }
3449 : }
3450 :
3451 2 : fileMeta := &manifest.TableMetadata{
3452 2 : TableNum: base.PhysicalTableFileNum(t.ObjMeta.DiskFileNum),
3453 2 : CreationTime: t.CreationTime.Unix(),
3454 2 : Size: t.WriterMeta.Size,
3455 2 : SmallestSeqNum: t.WriterMeta.SmallestSeqNum,
3456 2 : LargestSeqNum: t.WriterMeta.LargestSeqNum,
3457 2 : BlobReferences: t.BlobReferences,
3458 2 : BlobReferenceDepth: t.BlobReferenceDepth,
3459 2 : }
3460 2 : if c.flush.flushables == nil {
3461 2 : // Set the file's LargestSeqNumAbsolute to be the maximum value of any
3462 2 : // of the compaction's input sstables.
3463 2 : // TODO(jackson): This could be narrowed to be the maximum of input
3464 2 : // sstables that overlap the output sstable's key range.
3465 2 : fileMeta.LargestSeqNumAbsolute = inputLargestSeqNumAbsolute
3466 2 : } else {
3467 2 : fileMeta.LargestSeqNumAbsolute = t.WriterMeta.LargestSeqNum
3468 2 : }
3469 2 : fileMeta.InitPhysicalBacking()
3470 2 :
3471 2 : // If the file didn't contain any range deletions, we can fill its
3472 2 : // table stats now, avoiding unnecessarily loading the table later.
3473 2 : maybeSetStatsFromProperties(
3474 2 : fileMeta.PhysicalMeta(), &t.WriterMeta.Properties.CommonProperties, c.logger,
3475 2 : )
3476 2 :
3477 2 : if t.WriterMeta.HasPointKeys {
3478 2 : fileMeta.ExtendPointKeyBounds(c.comparer.Compare,
3479 2 : t.WriterMeta.SmallestPoint,
3480 2 : t.WriterMeta.LargestPoint)
3481 2 : }
3482 2 : if t.WriterMeta.HasRangeDelKeys {
3483 2 : fileMeta.ExtendPointKeyBounds(c.comparer.Compare,
3484 2 : t.WriterMeta.SmallestRangeDel,
3485 2 : t.WriterMeta.LargestRangeDel)
3486 2 : }
3487 2 : if t.WriterMeta.HasRangeKeys {
3488 2 : fileMeta.ExtendRangeKeyBounds(c.comparer.Compare,
3489 2 : t.WriterMeta.SmallestRangeKey,
3490 2 : t.WriterMeta.LargestRangeKey)
3491 2 : }
3492 :
3493 2 : ve.NewTables[i] = manifest.NewTableEntry{
3494 2 : Level: c.outputLevel.level,
3495 2 : Meta: fileMeta,
3496 2 : }
3497 2 :
3498 2 : // Update metrics.
3499 2 : if c.flush.flushables == nil {
3500 2 : outputMetrics.TablesCompacted++
3501 2 : outputMetrics.TableBytesCompacted += fileMeta.Size
3502 2 : } else {
3503 2 : outputMetrics.TablesFlushed++
3504 2 : outputMetrics.TableBytesFlushed += fileMeta.Size
3505 2 : }
3506 2 : outputMetrics.EstimatedReferencesSize += fileMeta.EstimatedReferenceSize()
3507 2 : outputMetrics.BlobBytesReadEstimate += fileMeta.EstimatedReferenceSize()
3508 2 : outputMetrics.TablesSize += int64(fileMeta.Size)
3509 2 : outputMetrics.TablesCount++
3510 2 : outputMetrics.Additional.BytesWrittenDataBlocks += t.WriterMeta.Properties.DataSize
3511 2 : outputMetrics.Additional.BytesWrittenValueBlocks += t.WriterMeta.Properties.ValueBlocksSize
3512 : }
3513 :
3514 : // Sanity check that the tables are ordered and don't overlap.
3515 2 : for i := 1; i < len(ve.NewTables); i++ {
3516 2 : if ve.NewTables[i-1].Meta.Largest().IsUpperBoundFor(c.comparer.Compare, ve.NewTables[i].Meta.Smallest().UserKey) {
3517 0 : return nil, base.AssertionFailedf("pebble: compaction output tables overlap: %s and %s",
3518 0 : ve.NewTables[i-1].Meta.DebugString(c.comparer.FormatKey, true),
3519 0 : ve.NewTables[i].Meta.DebugString(c.comparer.FormatKey, true),
3520 0 : )
3521 0 : }
3522 : }
3523 :
3524 2 : return ve, nil
3525 : }
3526 :
3527 : // newCompactionOutputTable creates an object for a new table produced by a
3528 : // compaction or flush.
3529 : func (d *DB) newCompactionOutputTable(
3530 : jobID JobID, c *tableCompaction, writerOpts sstable.WriterOptions,
3531 2 : ) (objstorage.ObjectMetadata, sstable.RawWriter, error) {
3532 2 : writable, objMeta, err := d.newCompactionOutputObj(c, base.FileTypeTable)
3533 2 : if err != nil {
3534 1 : return objstorage.ObjectMetadata{}, nil, err
3535 1 : }
3536 2 : d.opts.EventListener.TableCreated(TableCreateInfo{
3537 2 : JobID: int(jobID),
3538 2 : Reason: c.kind.compactingOrFlushing(),
3539 2 : Path: d.objProvider.Path(objMeta),
3540 2 : FileNum: objMeta.DiskFileNum,
3541 2 : })
3542 2 : writerOpts.SetInternal(sstableinternal.WriterOptions{
3543 2 : CacheOpts: sstableinternal.CacheOptions{
3544 2 : CacheHandle: d.cacheHandle,
3545 2 : FileNum: objMeta.DiskFileNum,
3546 2 : },
3547 2 : })
3548 2 : tw := sstable.NewRawWriterWithCPUMeasurer(writable, writerOpts, c.grantHandle)
3549 2 : return objMeta, tw, nil
3550 : }
3551 :
3552 : // newCompactionOutputBlob creates an object for a new blob produced by a
3553 : // compaction or flush.
3554 : func (d *DB) newCompactionOutputBlob(
3555 : jobID JobID, c *tableCompaction,
3556 2 : ) (objstorage.Writable, objstorage.ObjectMetadata, error) {
3557 2 : writable, objMeta, err := d.newCompactionOutputObj(c, base.FileTypeBlob)
3558 2 : if err != nil {
3559 0 : return nil, objstorage.ObjectMetadata{}, err
3560 0 : }
3561 2 : d.opts.EventListener.BlobFileCreated(BlobFileCreateInfo{
3562 2 : JobID: int(jobID),
3563 2 : Reason: c.kind.compactingOrFlushing(),
3564 2 : Path: d.objProvider.Path(objMeta),
3565 2 : FileNum: objMeta.DiskFileNum,
3566 2 : })
3567 2 : return writable, objMeta, nil
3568 : }
3569 :
3570 : // newCompactionOutputObj creates an object produced by a compaction or flush.
3571 : func (d *DB) newCompactionOutputObj(
3572 : c *tableCompaction, typ base.FileType,
3573 2 : ) (objstorage.Writable, objstorage.ObjectMetadata, error) {
3574 2 : diskFileNum := d.mu.versions.getNextDiskFileNum()
3575 2 : ctx := context.TODO()
3576 2 :
3577 2 : if objiotracing.Enabled {
3578 0 : ctx = objiotracing.WithLevel(ctx, c.outputLevel.level)
3579 0 : if c.kind == compactionKindFlush {
3580 0 : ctx = objiotracing.WithReason(ctx, objiotracing.ForFlush)
3581 0 : } else {
3582 0 : ctx = objiotracing.WithReason(ctx, objiotracing.ForCompaction)
3583 0 : }
3584 : }
3585 :
3586 2 : writable, objMeta, err := d.objProvider.Create(ctx, typ, diskFileNum, c.objCreateOpts)
3587 2 : if err != nil {
3588 1 : return nil, objstorage.ObjectMetadata{}, err
3589 1 : }
3590 :
3591 2 : if c.kind != compactionKindFlush {
3592 2 : writable = &compactionWritable{
3593 2 : Writable: writable,
3594 2 : versions: d.mu.versions,
3595 2 : written: &c.metrics.bytesWritten,
3596 2 : }
3597 2 : }
3598 2 : return writable, objMeta, nil
3599 : }
3600 :
3601 : // validateVersionEdit validates that start and end keys across new and deleted
3602 : // files in a versionEdit pass the given validation function.
3603 : func validateVersionEdit(
3604 : ve *manifest.VersionEdit, vk base.ValidateKey, format base.FormatKey, logger Logger,
3605 2 : ) {
3606 2 : validateKey := func(f *manifest.TableMetadata, key []byte) {
3607 2 : if err := vk.Validate(key); err != nil {
3608 1 : logger.Fatalf("pebble: version edit validation failed (key=%s file=%s): %v", format(key), f, err)
3609 1 : }
3610 : }
3611 :
3612 : // Validate both new and deleted files.
3613 2 : for _, f := range ve.NewTables {
3614 2 : validateKey(f.Meta, f.Meta.Smallest().UserKey)
3615 2 : validateKey(f.Meta, f.Meta.Largest().UserKey)
3616 2 : }
3617 2 : for _, m := range ve.DeletedTables {
3618 2 : validateKey(m, m.Smallest().UserKey)
3619 2 : validateKey(m, m.Largest().UserKey)
3620 2 : }
3621 : }
3622 :
3623 2 : func getDiskWriteCategoryForCompaction(opts *Options, kind compactionKind) vfs.DiskWriteCategory {
3624 2 : if opts.EnableSQLRowSpillMetrics {
3625 0 : // In the scenario that the Pebble engine is used for SQL row spills the
3626 0 : // data written to the memtable will correspond to spills to disk and
3627 0 : // should be categorized as such.
3628 0 : return "sql-row-spill"
3629 2 : } else if kind == compactionKindFlush {
3630 2 : return "pebble-memtable-flush"
3631 2 : } else if kind == compactionKindBlobFileRewrite {
3632 1 : return "pebble-blob-file-rewrite"
3633 2 : } else {
3634 2 : return "pebble-compaction"
3635 2 : }
3636 : }
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