Line data    Source code

       1             : // Copyright 2019 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 metamorphic
       6             : 
       7             : import "github.com/cockroachdb/pebble/internal/randvar"
       8             : 
       9             : type opType int
      10             : 
      11             : const (
      12             :         batchAbort opType = iota
      13             :         batchCommit
      14             :         dbCheckpoint
      15             :         dbClose
      16             :         dbCompact
      17             :         dbFlush
      18             :         dbRatchetFormatMajorVersion
      19             :         dbRestart
      20             :         iterClose
      21             :         iterFirst
      22             :         iterLast
      23             :         iterNext
      24             :         iterNextWithLimit
      25             :         iterNextPrefix
      26             :         iterPrev
      27             :         iterPrevWithLimit
      28             :         iterSeekGE
      29             :         iterSeekGEWithLimit
      30             :         iterSeekLT
      31             :         iterSeekLTWithLimit
      32             :         iterSeekPrefixGE
      33             :         iterSetBounds
      34             :         iterSetOptions
      35             :         newBatch
      36             :         newIndexedBatch
      37             :         newIter
      38             :         newIterUsingClone
      39             :         newSnapshot
      40             :         readerGet
      41             :         snapshotClose
      42             :         writerApply
      43             :         writerDelete
      44             :         writerDeleteRange
      45             :         writerIngest
      46             :         writerMerge
      47             :         writerRangeKeyDelete
      48             :         writerRangeKeySet
      49             :         writerRangeKeyUnset
      50             :         writerSet
      51             :         writerSingleDelete
      52             : )
      53             : 
      54             : type config struct {
      55             :         // Weights for the operation mix to generate. ops[i] corresponds to the
      56             :         // weight for opType(i).
      57             :         ops []int
      58             : 
      59             :         // newPrefix configures the probability that when generating a new user key,
      60             :         // the generated key uses a new key prefix rather than an existing prefix
      61             :         // with a suffix.
      62             :         newPrefix float64
      63             :         // writeSuffixDist defines the distribution of key suffixes during writing.
      64             :         // It's a dynamic randvar to roughly emulate workloads with MVCC timestamps,
      65             :         // skewing towards most recent timestamps.
      66             :         writeSuffixDist randvar.Dynamic
      67             : 
      68             :         // TODO(peter): unimplemented
      69             :         // keyDist        randvar.Dynamic
      70             :         // keySizeDist    randvar.Static
      71             :         // valueSizeDist  randvar.Static
      72             :         // updateFrac     float64
      73             :         // lowerBoundFrac float64
      74             :         // upperBoundFrac float64
      75             : }
      76             : 
      77           1 : func defaultConfig() config {
      78           1 :         return config{
      79           1 :                 // dbClose is not in this list since it is deterministically generated once, at the end of the test.
      80           1 :                 ops: []int{
      81           1 :                         batchAbort:                  5,
      82           1 :                         batchCommit:                 5,
      83           1 :                         dbCheckpoint:                1,
      84           1 :                         dbCompact:                   1,
      85           1 :                         dbFlush:                     2,
      86           1 :                         dbRatchetFormatMajorVersion: 1,
      87           1 :                         dbRestart:                   2,
      88           1 :                         iterClose:                   5,
      89           1 :                         iterFirst:                   100,
      90           1 :                         iterLast:                    100,
      91           1 :                         iterNext:                    100,
      92           1 :                         iterNextWithLimit:           20,
      93           1 :                         iterNextPrefix:              20,
      94           1 :                         iterPrev:                    100,
      95           1 :                         iterPrevWithLimit:           20,
      96           1 :                         iterSeekGE:                  100,
      97           1 :                         iterSeekGEWithLimit:         20,
      98           1 :                         iterSeekLT:                  100,
      99           1 :                         iterSeekLTWithLimit:         20,
     100           1 :                         iterSeekPrefixGE:            100,
     101           1 :                         iterSetBounds:               100,
     102           1 :                         iterSetOptions:              10,
     103           1 :                         newBatch:                    5,
     104           1 :                         newIndexedBatch:             5,
     105           1 :                         newIter:                     10,
     106           1 :                         newIterUsingClone:           5,
     107           1 :                         newSnapshot:                 10,
     108           1 :                         readerGet:                   100,
     109           1 :                         snapshotClose:               10,
     110           1 :                         writerApply:                 10,
     111           1 :                         writerDelete:                100,
     112           1 :                         writerDeleteRange:           50,
     113           1 :                         writerIngest:                100,
     114           1 :                         writerMerge:                 100,
     115           1 :                         writerRangeKeySet:           10,
     116           1 :                         writerRangeKeyUnset:         10,
     117           1 :                         writerRangeKeyDelete:        5,
     118           1 :                         writerSet:                   100,
     119           1 :                         writerSingleDelete:          50,
     120           1 :                 },
     121           1 :                 // Use a new prefix 75% of the time (and 25% of the time use an existing
     122           1 :                 // prefix with an alternative suffix).
     123           1 :                 newPrefix: 0.75,
     124           1 :                 // Use a skewed distribution of suffixes to mimic MVCC timestamps. The
     125           1 :                 // range will be widened whenever a suffix is found to already be in use
     126           1 :                 // for a particular prefix.
     127           1 :                 writeSuffixDist: mustDynamic(randvar.NewSkewedLatest(0, 1, 0.99)),
     128           1 :         }
     129           1 : }
     130             : 
     131           1 : func mustDynamic(dyn randvar.Dynamic, err error) randvar.Dynamic {
     132           1 :         if err != nil {
     133           0 :                 panic(err)
     134             :         }
     135           1 :         return dyn
     136             : }