/src/postgres/src/include/executor/instrument_node.h

Source
/*-------------------------------------------------------------------------
 *
 * instrument_node.h
 *    Definitions for node-specific support for parallel query instrumentation
 *
 * These structs purposely contain no pointers because they are copied
 * across processes during parallel query execution.  Each worker copies its
 * individual information into the container struct at executor shutdown time,
 * to allow the leader to display the information in EXPLAIN ANALYZE.
 *
 * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 * src/include/executor/instrument_node.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef INSTRUMENT_NODE_H
#define INSTRUMENT_NODE_H

/*
 * Offset added to plan_node_id to create a second TOC key for per-worker scan
 * instrumentation. Instrumentation and parallel-awareness are independent, so
 * separate DSM chunks let each be allocated and initialized only when needed.
 * In the future, if nodes need more DSM allocations, we would need a more
 * robust system.
 */
#define PARALLEL_KEY_SCAN_INSTRUMENT_OFFSET UINT64CONST(0xD000000000000000)

/* ---------------------
 *  Instrumentation information for aggregate function execution
 * ---------------------
 */
typedef struct AggregateInstrumentation
{
  Size    hash_mem_peak;  /* peak hash table memory usage */
  uint64    hash_disk_used; /* kB of disk space used */
  int     hash_batches_used;  /* batches used during entire execution */
} AggregateInstrumentation;

/*
 * Shared memory container for per-worker aggregate information
 */
typedef struct SharedAggInfo
{
  int     num_workers;
  AggregateInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedAggInfo;


/* ---------------------
 *  Instrumentation information about read streams and I/O
 * ---------------------
 */
typedef struct IOStats
{
  /* number of buffers returned to consumer (for averaging distance) */
  uint64    prefetch_count;

  /* sum of pinned_buffers sampled at each buffer return */
  uint64    distance_sum;

  /* maximum actual pinned_buffers observed during the scan */
  int16   distance_max;

  /* maximum possible look-ahead distance (max_pinned_buffers) */
  int16   distance_capacity;

  /* number of waits for a read (for the I/O) */
  uint64    wait_count;

  /* I/O stats */
  uint64    io_count;   /* number of I/Os */
  uint64    io_nblocks;   /* sum of blocks for all I/Os */
  uint64    io_in_progress; /* sum of in-progress I/Os */
} IOStats;

typedef struct TableScanInstrumentation
{
  IOStats   io;
} TableScanInstrumentation;

/* merge IO statistics from 'src' into 'dst' */
static inline void
AccumulateIOStats(IOStats *dst, IOStats *src)
{
  dst->prefetch_count += src->prefetch_count;
  dst->distance_sum += src->distance_sum;
  if (src->distance_max > dst->distance_max)
    dst->distance_max = src->distance_max;
  if (src->distance_capacity > dst->distance_capacity)
    dst->distance_capacity = src->distance_capacity;
  dst->wait_count += src->wait_count;
  dst->io_count += src->io_count;
  dst->io_nblocks += src->io_nblocks;
  dst->io_in_progress += src->io_in_progress;
}


/* ---------------------
 *  Instrumentation information for index scans (used by all AM interfaces)
 * ---------------------
 */
typedef struct IndexScanInstrumentation
{
  /* Index search count (incremented with pgstat_count_index_scan call) */
  uint64    nsearches;

  /* Table tuples fetched count (incremented during index-only scans) */
  uint64    ntabletuplefetches;
} IndexScanInstrumentation;

/*
 * Shared memory container for per-worker information
 */
typedef struct SharedIndexScanInstrumentation
{
  int     num_workers;
  IndexScanInstrumentation winstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedIndexScanInstrumentation;


/* ---------------------
 *  Instrumentation information for bitmap heap scans
 *
 *    exact_pages      total number of exact pages retrieved
 *    lossy_pages      total number of lossy pages retrieved
 * ---------------------
 */
typedef struct BitmapHeapScanInstrumentation
{
  uint64    exact_pages;
  uint64    lossy_pages;
  TableScanInstrumentation stats;
} BitmapHeapScanInstrumentation;

/*
 * Shared memory container for per-worker information
 */
typedef struct SharedBitmapHeapInstrumentation
{
  int     num_workers;
  BitmapHeapScanInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedBitmapHeapInstrumentation;


/* ---------------------
 *  Instrumentation information for Memoize
 * ---------------------
 */
typedef struct MemoizeInstrumentation
{
  uint64    cache_hits;   /* number of rescans where we've found the
                 * scan parameters values to be cached */
  uint64    cache_misses; /* number of rescans where we've not found the
                 * scan parameters values to be cached */
  uint64    cache_evictions;  /* number of cache entries removed due to
                   * the need to free memory */
  uint64    cache_overflows;  /* number of times we've had to bypass the
                   * cache when filling it due to not being
                   * able to free enough space to store the
                   * current scan's tuples */
  uint64    mem_peak;   /* peak memory usage in bytes */
} MemoizeInstrumentation;

/*
 * Shared memory container for per-worker memoize information
 */
typedef struct SharedMemoizeInfo
{
  int     num_workers;
  MemoizeInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedMemoizeInfo;


/* ---------------------
 *  Instrumentation information for Sorts.
 * ---------------------
 */

typedef enum
{
  SORT_SPACE_TYPE_DISK,
  SORT_SPACE_TYPE_MEMORY,
} TuplesortSpaceType;

/*
 * The parallel-sort infrastructure relies on having a zero TuplesortMethod
 * to indicate that a worker never did anything, so we assign zero to
 * SORT_TYPE_STILL_IN_PROGRESS.  The other values of this enum can be
 * OR'ed together to represent a situation where different workers used
 * different methods, so we need a separate bit for each one.  Keep the
 * NUM_TUPLESORTMETHODS constant in sync with the number of bits!
 */
typedef enum
{
  SORT_TYPE_STILL_IN_PROGRESS = 0,
  SORT_TYPE_TOP_N_HEAPSORT = 1 << 0,
  SORT_TYPE_QUICKSORT = 1 << 1,
  SORT_TYPE_EXTERNAL_SORT = 1 << 2,
  SORT_TYPE_EXTERNAL_MERGE = 1 << 3,
} TuplesortMethod;
#define NUM_TUPLESORTMETHODS 4

typedef struct TuplesortInstrumentation
{
  TuplesortMethod sortMethod; /* sort algorithm used */
  TuplesortSpaceType spaceType; /* type of space spaceUsed represents */
  int64   spaceUsed;    /* space consumption, in kB */
} TuplesortInstrumentation;

/*
 * Shared memory container for per-worker sort information
 */
typedef struct SharedSortInfo
{
  int     num_workers;
  TuplesortInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedSortInfo;


/* ---------------------
 *   Instrumentation information for nodeHash.c
 * ---------------------
 */
typedef struct HashInstrumentation
{
  int     nbuckets;   /* number of buckets at end of execution */
  int     nbuckets_original;  /* planned number of buckets */
  int     nbatch;     /* number of batches at end of execution */
  int     nbatch_original;  /* planned number of batches */
  Size    space_peak;   /* peak memory usage in bytes */
} HashInstrumentation;

/*
 * Shared memory container for per-worker information
 */
typedef struct SharedHashInfo
{
  int     num_workers;
  HashInstrumentation hinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedHashInfo;


/* ---------------------
 *   Instrumentation information for IncrementalSort
 * ---------------------
 */
typedef struct IncrementalSortGroupInfo
{
  int64   groupCount;
  int64   maxDiskSpaceUsed;
  int64   totalDiskSpaceUsed;
  int64   maxMemorySpaceUsed;
  int64   totalMemorySpaceUsed;
  uint32    sortMethods;  /* bitmask of TuplesortMethod */
} IncrementalSortGroupInfo;

typedef struct IncrementalSortInfo
{
  IncrementalSortGroupInfo fullsortGroupInfo;
  IncrementalSortGroupInfo prefixsortGroupInfo;
} IncrementalSortInfo;

/* Shared memory container for per-worker incremental sort information */
typedef struct SharedIncrementalSortInfo
{
  int     num_workers;
  IncrementalSortInfo sinfo[FLEXIBLE_ARRAY_MEMBER];
} SharedIncrementalSortInfo;


/* ---------------------
 *  Instrumentation information for sequential scans
 * ---------------------
 */
typedef struct SeqScanInstrumentation
{
  TableScanInstrumentation stats;
} SeqScanInstrumentation;

/*
 * Shared memory container for per-worker information
 */
typedef struct SharedSeqScanInstrumentation
{
  int     num_workers;
  SeqScanInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedSeqScanInstrumentation;


/*
 *  Instrumentation information for TID range scans
 */
typedef struct TidRangeScanInstrumentation
{
  TableScanInstrumentation stats;
} TidRangeScanInstrumentation;

/*
 * Shared memory container for per-worker information
 */
typedef struct SharedTidRangeScanInstrumentation
{
  int     num_workers;
  TidRangeScanInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER];
} SharedTidRangeScanInstrumentation;

#endif              /* INSTRUMENT_NODE_H */

Coverage Report

Created: 2026-09-28 06:55

Line	Count	Source
1		/*-------------------------------------------------------------------------
2		*
3		* instrument_node.h
4		* Definitions for node-specific support for parallel query instrumentation
5		*
6		* These structs purposely contain no pointers because they are copied
7		* across processes during parallel query execution. Each worker copies its
8		* individual information into the container struct at executor shutdown time,
9		* to allow the leader to display the information in EXPLAIN ANALYZE.
10		*
11		* Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
12		* Portions Copyright (c) 1994, Regents of the University of California
13		*
14		* src/include/executor/instrument_node.h
15		*
16		*-------------------------------------------------------------------------
17		*/
18		#ifndef INSTRUMENT_NODE_H
19		#define INSTRUMENT_NODE_H
20
21		/*
22		* Offset added to plan_node_id to create a second TOC key for per-worker scan
23		* instrumentation. Instrumentation and parallel-awareness are independent, so
24		* separate DSM chunks let each be allocated and initialized only when needed.
25		* In the future, if nodes need more DSM allocations, we would need a more
26		* robust system.
27		*/
28	0	#define PARALLEL_KEY_SCAN_INSTRUMENT_OFFSET UINT64CONST(0xD000000000000000)
29
30		/* ---------------------
31		* Instrumentation information for aggregate function execution
32		* ---------------------
33		*/
34		typedef struct AggregateInstrumentation
35		{
36		Size hash_mem_peak; /* peak hash table memory usage */
37		uint64 hash_disk_used; /* kB of disk space used */
38		int hash_batches_used; /* batches used during entire execution */
39		} AggregateInstrumentation;