PostgreSQL Source Code  git master
nodeMemoize.c File Reference
#include "postgres.h"
#include "common/hashfn.h"
#include "executor/executor.h"
#include "executor/nodeMemoize.h"
#include "lib/ilist.h"
#include "miscadmin.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "lib/simplehash.h"
Include dependency graph for nodeMemoize.c:

Go to the source code of this file.

Data Structures

struct  MemoizeTuple
 
struct  MemoizeKey
 
struct  MemoizeEntry
 

Macros

#define MEMO_CACHE_LOOKUP   1 /* Attempt to perform a cache lookup */
 
#define MEMO_CACHE_FETCH_NEXT_TUPLE   2 /* Get another tuple from the cache */
 
#define MEMO_FILLING_CACHE   3 /* Read outer node to fill cache */
 
#define MEMO_CACHE_BYPASS_MODE
 
#define MEMO_END_OF_SCAN   5 /* Ready for rescan */
 
#define EMPTY_ENTRY_MEMORY_BYTES(e)
 
#define CACHE_TUPLE_BYTES(t)
 
#define SH_PREFIX   memoize
 
#define SH_ELEMENT_TYPE   MemoizeEntry
 
#define SH_KEY_TYPE   MemoizeKey *
 
#define SH_SCOPE   static inline
 
#define SH_DECLARE
 
#define SH_PREFIX   memoize
 
#define SH_ELEMENT_TYPE   MemoizeEntry
 
#define SH_KEY_TYPE   MemoizeKey *
 
#define SH_KEY   key
 
#define SH_HASH_KEY(tb, key)   MemoizeHash_hash(tb, key)
 
#define SH_EQUAL(tb, a, b)   MemoizeHash_equal(tb, a, b)
 
#define SH_SCOPE   static inline
 
#define SH_STORE_HASH
 
#define SH_GET_HASH(tb, a)   a->hash
 
#define SH_DEFINE
 

Typedefs

typedef struct MemoizeTuple MemoizeTuple
 
typedef struct MemoizeKey MemoizeKey
 
typedef struct MemoizeEntry MemoizeEntry
 

Functions

static uint32 MemoizeHash_hash (struct memoize_hash *tb, const MemoizeKey *key)
 
static bool MemoizeHash_equal (struct memoize_hash *tb, const MemoizeKey *key1, const MemoizeKey *key2)
 
static void build_hash_table (MemoizeState *mstate, uint32 size)
 
static void prepare_probe_slot (MemoizeState *mstate, MemoizeKey *key)
 
static void entry_purge_tuples (MemoizeState *mstate, MemoizeEntry *entry)
 
static void remove_cache_entry (MemoizeState *mstate, MemoizeEntry *entry)
 
static void cache_purge_all (MemoizeState *mstate)
 
static bool cache_reduce_memory (MemoizeState *mstate, MemoizeKey *specialkey)
 
static MemoizeEntrycache_lookup (MemoizeState *mstate, bool *found)
 
static bool cache_store_tuple (MemoizeState *mstate, TupleTableSlot *slot)
 
static TupleTableSlotExecMemoize (PlanState *pstate)
 
MemoizeStateExecInitMemoize (Memoize *node, EState *estate, int eflags)
 
void ExecEndMemoize (MemoizeState *node)
 
void ExecReScanMemoize (MemoizeState *node)
 
double ExecEstimateCacheEntryOverheadBytes (double ntuples)
 
void ExecMemoizeEstimate (MemoizeState *node, ParallelContext *pcxt)
 
void ExecMemoizeInitializeDSM (MemoizeState *node, ParallelContext *pcxt)
 
void ExecMemoizeInitializeWorker (MemoizeState *node, ParallelWorkerContext *pwcxt)
 
void ExecMemoizeRetrieveInstrumentation (MemoizeState *node)
 

Macro Definition Documentation

◆ CACHE_TUPLE_BYTES

#define CACHE_TUPLE_BYTES (   t)
Value:
(sizeof(MemoizeTuple) + \
(t)->mintuple->t_len)
struct MemoizeTuple MemoizeTuple

Definition at line 89 of file nodeMemoize.c.

◆ EMPTY_ENTRY_MEMORY_BYTES

#define EMPTY_ENTRY_MEMORY_BYTES (   e)
Value:
(sizeof(MemoizeEntry) + \
sizeof(MemoizeKey) + \
(e)->key->params->t_len);
struct MemoizeEntry MemoizeEntry
e
Definition: preproc-init.c:82

Definition at line 86 of file nodeMemoize.c.

◆ MEMO_CACHE_BYPASS_MODE

#define MEMO_CACHE_BYPASS_MODE
Value:
4 /* Bypass mode. Just read from our
* subplan without caching anything */

Definition at line 81 of file nodeMemoize.c.

◆ MEMO_CACHE_FETCH_NEXT_TUPLE

#define MEMO_CACHE_FETCH_NEXT_TUPLE   2 /* Get another tuple from the cache */

Definition at line 79 of file nodeMemoize.c.

◆ MEMO_CACHE_LOOKUP

#define MEMO_CACHE_LOOKUP   1 /* Attempt to perform a cache lookup */

Definition at line 78 of file nodeMemoize.c.

◆ MEMO_END_OF_SCAN

#define MEMO_END_OF_SCAN   5 /* Ready for rescan */

Definition at line 82 of file nodeMemoize.c.

◆ MEMO_FILLING_CACHE

#define MEMO_FILLING_CACHE   3 /* Read outer node to fill cache */

Definition at line 80 of file nodeMemoize.c.

◆ SH_DECLARE

#define SH_DECLARE

Definition at line 129 of file nodeMemoize.c.

◆ SH_DEFINE

#define SH_DEFINE

Definition at line 147 of file nodeMemoize.c.

◆ SH_ELEMENT_TYPE [1/2]

#define SH_ELEMENT_TYPE   MemoizeEntry

Definition at line 139 of file nodeMemoize.c.

◆ SH_ELEMENT_TYPE [2/2]

#define SH_ELEMENT_TYPE   MemoizeEntry

Definition at line 139 of file nodeMemoize.c.

◆ SH_EQUAL

#define SH_EQUAL (   tb,
  a,
  b 
)    MemoizeHash_equal(tb, a, b)

Definition at line 143 of file nodeMemoize.c.

◆ SH_GET_HASH

#define SH_GET_HASH (   tb,
  a 
)    a->hash

Definition at line 146 of file nodeMemoize.c.

◆ SH_HASH_KEY

#define SH_HASH_KEY (   tb,
  key 
)    MemoizeHash_hash(tb, key)

Definition at line 142 of file nodeMemoize.c.

◆ SH_KEY

#define SH_KEY   key

Definition at line 141 of file nodeMemoize.c.

◆ SH_KEY_TYPE [1/2]

#define SH_KEY_TYPE   MemoizeKey *

Definition at line 140 of file nodeMemoize.c.

◆ SH_KEY_TYPE [2/2]

#define SH_KEY_TYPE   MemoizeKey *

Definition at line 140 of file nodeMemoize.c.

◆ SH_PREFIX [1/2]

#define SH_PREFIX   memoize

Definition at line 138 of file nodeMemoize.c.

◆ SH_PREFIX [2/2]

#define SH_PREFIX   memoize

Definition at line 138 of file nodeMemoize.c.

◆ SH_SCOPE [1/2]

#define SH_SCOPE   static inline

Definition at line 144 of file nodeMemoize.c.

◆ SH_SCOPE [2/2]

#define SH_SCOPE   static inline

Definition at line 144 of file nodeMemoize.c.

◆ SH_STORE_HASH

#define SH_STORE_HASH

Definition at line 145 of file nodeMemoize.c.

Typedef Documentation

◆ MemoizeEntry

typedef struct MemoizeEntry MemoizeEntry

◆ MemoizeKey

typedef struct MemoizeKey MemoizeKey

◆ MemoizeTuple

typedef struct MemoizeTuple MemoizeTuple

Function Documentation

◆ build_hash_table()

static void build_hash_table ( MemoizeState mstate,
uint32  size 
)
static

Definition at line 282 of file nodeMemoize.c.

284 {
285  Assert(mstate->hashtable == NULL);
286 
287  /* Make a guess at a good size when we're not given a valid size. */
288  if (size == 0)
289  size = 1024;
290 
291  /* memoize_create will convert the size to a power of 2 */
292  mstate->hashtable = memoize_create(mstate->tableContext, size, mstate);
#define Assert(condition)
Definition: c.h:858
static pg_noinline void Size size
Definition: slab.c:607
MemoryContext tableContext
Definition: execnodes.h:2284
struct memoize_hash * hashtable
Definition: execnodes.h:2273

References Assert, MemoizeState::hashtable, size, and MemoizeState::tableContext.

Referenced by ExecMemoize().

◆ cache_lookup()

static MemoizeEntry* cache_lookup ( MemoizeState mstate,
bool found 
)
static

Definition at line 527 of file nodeMemoize.c.

529 {
530  MemoizeKey *key;
531  MemoizeEntry *entry;
532  MemoryContext oldcontext;
533 
534  /* prepare the probe slot with the current scan parameters */
535  prepare_probe_slot(mstate, NULL);
536 
537  /*
538  * Add the new entry to the cache. No need to pass a valid key since the
539  * hash function uses mstate's probeslot, which we populated above.
540  */
541  entry = memoize_insert(mstate->hashtable, NULL, found);
542 
543  if (*found)
544  {
545  /*
546  * Move existing entry to the tail of the LRU list to mark it as the
547  * most recently used item.
548  */
549  dlist_move_tail(&mstate->lru_list, &entry->key->lru_node);
550 
551  return entry;
552  }
553 
554  oldcontext = MemoryContextSwitchTo(mstate->tableContext);
555 
556  /* Allocate a new key */
557  entry->key = key = (MemoizeKey *) palloc(sizeof(MemoizeKey));
558  key->params = ExecCopySlotMinimalTuple(mstate->probeslot);
559 
560  /* Update the total cache memory utilization */
561  mstate->mem_used += EMPTY_ENTRY_MEMORY_BYTES(entry);
562 
563  /* Initialize this entry */
564  entry->complete = false;
565  entry->tuplehead = NULL;
566 
567  /*
568  * Since this is the most recently used entry, push this entry onto the
569  * end of the LRU list.
570  */
571  dlist_push_tail(&mstate->lru_list, &entry->key->lru_node);
572 
573  mstate->last_tuple = NULL;
574 
575  MemoryContextSwitchTo(oldcontext);
576 
577  /*
578  * If we've gone over our memory budget, then we'll free up some space in
579  * the cache.
580  */
581  if (mstate->mem_used > mstate->mem_limit)
582  {
583  /*
584  * Try to free up some memory. It's highly unlikely that we'll fail
585  * to do so here since the entry we've just added is yet to contain
586  * any tuples and we're able to remove any other entry to reduce the
587  * memory consumption.
588  */
589  if (unlikely(!cache_reduce_memory(mstate, key)))
590  return NULL;
591 
592  /*
593  * The process of removing entries from the cache may have caused the
594  * code in simplehash.h to shuffle elements to earlier buckets in the
595  * hash table. If it has, we'll need to find the entry again by
596  * performing a lookup. Fortunately, we can detect if this has
597  * happened by seeing if the entry is still in use and that the key
598  * pointer matches our expected key.
599  */
600  if (entry->status != memoize_SH_IN_USE || entry->key != key)
601  {
602  /*
603  * We need to repopulate the probeslot as lookups performed during
604  * the cache evictions above will have stored some other key.
605  */
606  prepare_probe_slot(mstate, key);
607 
608  /* Re-find the newly added entry */
609  entry = memoize_lookup(mstate->hashtable, NULL);
610  Assert(entry != NULL);
611  }
612  }
613 
614  return entry;
#define unlikely(x)
Definition: c.h:311
static void dlist_push_tail(dlist_head *head, dlist_node *node)
Definition: ilist.h:364
static void dlist_move_tail(dlist_head *head, dlist_node *node)
Definition: ilist.h:486
void * palloc(Size size)
Definition: mcxt.c:1316
static bool cache_reduce_memory(MemoizeState *mstate, MemoizeKey *specialkey)
Definition: nodeMemoize.c:439
static void prepare_probe_slot(MemoizeState *mstate, MemoizeKey *key)
Definition: nodeMemoize.c:301
#define EMPTY_ENTRY_MEMORY_BYTES(e)
Definition: nodeMemoize.c:86
MemoryContextSwitchTo(old_ctx)
MemoizeKey * key
Definition: nodeMemoize.c:116
MemoizeTuple * tuplehead
Definition: nodeMemoize.c:117
dlist_node lru_node
Definition: nodeMemoize.c:107
uint64 mem_used
Definition: execnodes.h:2282
TupleTableSlot * probeslot
Definition: execnodes.h:2276
dlist_head lru_list
Definition: execnodes.h:2285
uint64 mem_limit
Definition: execnodes.h:2283
struct MemoizeTuple * last_tuple
Definition: execnodes.h:2286
static MinimalTuple ExecCopySlotMinimalTuple(TupleTableSlot *slot)
Definition: tuptable.h:492

References Assert, cache_reduce_memory(), MemoizeEntry::complete, dlist_move_tail(), dlist_push_tail(), EMPTY_ENTRY_MEMORY_BYTES, ExecCopySlotMinimalTuple(), MemoizeState::hashtable, MemoizeEntry::key, sort-test::key, MemoizeState::last_tuple, MemoizeState::lru_list, MemoizeKey::lru_node, MemoizeState::mem_limit, MemoizeState::mem_used, MemoryContextSwitchTo(), palloc(), prepare_probe_slot(), MemoizeState::probeslot, MemoizeEntry::status, MemoizeState::tableContext, MemoizeEntry::tuplehead, and unlikely.

Referenced by ExecMemoize().

◆ cache_purge_all()

static void cache_purge_all ( MemoizeState mstate)
static

Definition at line 401 of file nodeMemoize.c.

403 {
404  uint64 evictions = 0;
405 
406  if (mstate->hashtable != NULL)
407  evictions = mstate->hashtable->members;
408 
409  /*
410  * Likely the most efficient way to remove all items is to just reset the
411  * memory context for the cache and then rebuild a fresh hash table. This
412  * saves having to remove each item one by one and pfree each cached tuple
413  */
415 
416  /* NULLify so we recreate the table on the next call */
417  mstate->hashtable = NULL;
418 
419  /* reset the LRU list */
420  dlist_init(&mstate->lru_list);
421  mstate->last_tuple = NULL;
422  mstate->entry = NULL;
423 
424  mstate->mem_used = 0;
425 
426  /* XXX should we add something new to track these purges? */
427  mstate->stats.cache_evictions += evictions; /* Update Stats */
static void dlist_init(dlist_head *head)
Definition: ilist.h:314
void MemoryContextReset(MemoryContext context)
Definition: mcxt.c:383
struct MemoizeEntry * entry
Definition: execnodes.h:2290
MemoizeInstrumentation stats
Definition: execnodes.h:2296

References MemoizeInstrumentation::cache_evictions, dlist_init(), MemoizeState::entry, MemoizeState::hashtable, MemoizeState::last_tuple, MemoizeState::lru_list, MemoizeState::mem_used, MemoryContextReset(), MemoizeState::stats, and MemoizeState::tableContext.

Referenced by ExecReScanMemoize().

◆ cache_reduce_memory()

static bool cache_reduce_memory ( MemoizeState mstate,
MemoizeKey specialkey 
)
static

Definition at line 439 of file nodeMemoize.c.

441 {
442  bool specialkey_intact = true; /* for now */
443  dlist_mutable_iter iter;
444  uint64 evictions = 0;
445 
446  /* Update peak memory usage */
447  if (mstate->mem_used > mstate->stats.mem_peak)
448  mstate->stats.mem_peak = mstate->mem_used;
449 
450  /* We expect only to be called when we've gone over budget on memory */
451  Assert(mstate->mem_used > mstate->mem_limit);
452 
453  /* Start the eviction process starting at the head of the LRU list. */
454  dlist_foreach_modify(iter, &mstate->lru_list)
455  {
456  MemoizeKey *key = dlist_container(MemoizeKey, lru_node, iter.cur);
457  MemoizeEntry *entry;
458 
459  /*
460  * Populate the hash probe slot in preparation for looking up this LRU
461  * entry.
462  */
463  prepare_probe_slot(mstate, key);
464 
465  /*
466  * Ideally the LRU list pointers would be stored in the entry itself
467  * rather than in the key. Unfortunately, we can't do that as the
468  * simplehash.h code may resize the table and allocate new memory for
469  * entries which would result in those pointers pointing to the old
470  * buckets. However, it's fine to use the key to store this as that's
471  * only referenced by a pointer in the entry, which of course follows
472  * the entry whenever the hash table is resized. Since we only have a
473  * pointer to the key here, we must perform a hash table lookup to
474  * find the entry that the key belongs to.
475  */
476  entry = memoize_lookup(mstate->hashtable, NULL);
477 
478  /*
479  * Sanity check that we found the entry belonging to the LRU list
480  * item. A misbehaving hash or equality function could cause the
481  * entry not to be found or the wrong entry to be found.
482  */
483  if (unlikely(entry == NULL || entry->key != key))
484  elog(ERROR, "could not find memoization table entry");
485 
486  /*
487  * If we're being called to free memory while the cache is being
488  * populated with new tuples, then we'd better take some care as we
489  * could end up freeing the entry which 'specialkey' belongs to.
490  * Generally callers will pass 'specialkey' as the key for the cache
491  * entry which is currently being populated, so we must set
492  * 'specialkey_intact' to false to inform the caller the specialkey
493  * entry has been removed.
494  */
495  if (key == specialkey)
496  specialkey_intact = false;
497 
498  /*
499  * Finally remove the entry. This will remove from the LRU list too.
500  */
501  remove_cache_entry(mstate, entry);
502 
503  evictions++;
504 
505  /* Exit if we've freed enough memory */
506  if (mstate->mem_used <= mstate->mem_limit)
507  break;
508  }
509 
510  mstate->stats.cache_evictions += evictions; /* Update Stats */
511 
512  return specialkey_intact;
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
#define dlist_foreach_modify(iter, lhead)
Definition: ilist.h:640
#define dlist_container(type, membername, ptr)
Definition: ilist.h:593
static void remove_cache_entry(MemoizeState *mstate, MemoizeEntry *entry)
Definition: nodeMemoize.c:373
dlist_node * cur
Definition: ilist.h:200

References Assert, MemoizeInstrumentation::cache_evictions, dlist_mutable_iter::cur, dlist_container, dlist_foreach_modify, elog, ERROR, MemoizeState::hashtable, MemoizeEntry::key, sort-test::key, MemoizeState::lru_list, MemoizeState::mem_limit, MemoizeInstrumentation::mem_peak, MemoizeState::mem_used, prepare_probe_slot(), remove_cache_entry(), MemoizeState::stats, and unlikely.

Referenced by cache_lookup(), and cache_store_tuple().

◆ cache_store_tuple()

static bool cache_store_tuple ( MemoizeState mstate,
TupleTableSlot slot 
)
static

Definition at line 624 of file nodeMemoize.c.

626 {
627  MemoizeTuple *tuple;
628  MemoizeEntry *entry = mstate->entry;
629  MemoryContext oldcontext;
630 
631  Assert(slot != NULL);
632  Assert(entry != NULL);
633 
634  oldcontext = MemoryContextSwitchTo(mstate->tableContext);
635 
636  tuple = (MemoizeTuple *) palloc(sizeof(MemoizeTuple));
637  tuple->mintuple = ExecCopySlotMinimalTuple(slot);
638  tuple->next = NULL;
639 
640  /* Account for the memory we just consumed */
641  mstate->mem_used += CACHE_TUPLE_BYTES(tuple);
642 
643  if (entry->tuplehead == NULL)
644  {
645  /*
646  * This is the first tuple for this entry, so just point the list head
647  * to it.
648  */
649  entry->tuplehead = tuple;
650  }
651  else
652  {
653  /* push this tuple onto the tail of the list */
654  mstate->last_tuple->next = tuple;
655  }
656 
657  mstate->last_tuple = tuple;
658  MemoryContextSwitchTo(oldcontext);
659 
660  /*
661  * If we've gone over our memory budget then free up some space in the
662  * cache.
663  */
664  if (mstate->mem_used > mstate->mem_limit)
665  {
666  MemoizeKey *key = entry->key;
667 
668  if (!cache_reduce_memory(mstate, key))
669  return false;
670 
671  /*
672  * The process of removing entries from the cache may have caused the
673  * code in simplehash.h to shuffle elements to earlier buckets in the
674  * hash table. If it has, we'll need to find the entry again by
675  * performing a lookup. Fortunately, we can detect if this has
676  * happened by seeing if the entry is still in use and that the key
677  * pointer matches our expected key.
678  */
679  if (entry->status != memoize_SH_IN_USE || entry->key != key)
680  {
681  /*
682  * We need to repopulate the probeslot as lookups performed during
683  * the cache evictions above will have stored some other key.
684  */
685  prepare_probe_slot(mstate, key);
686 
687  /* Re-find the entry */
688  mstate->entry = entry = memoize_lookup(mstate->hashtable, NULL);
689  Assert(entry != NULL);
690  }
691  }
692 
693  return true;
#define CACHE_TUPLE_BYTES(t)
Definition: nodeMemoize.c:89
MinimalTuple mintuple
Definition: nodeMemoize.c:95
struct MemoizeTuple * next
Definition: nodeMemoize.c:96

References Assert, cache_reduce_memory(), CACHE_TUPLE_BYTES, MemoizeState::entry, ExecCopySlotMinimalTuple(), MemoizeState::hashtable, MemoizeEntry::key, sort-test::key, MemoizeState::last_tuple, MemoizeState::mem_limit, MemoizeState::mem_used, MemoryContextSwitchTo(), MemoizeTuple::mintuple, MemoizeTuple::next, palloc(), prepare_probe_slot(), MemoizeEntry::status, MemoizeState::tableContext, and MemoizeEntry::tuplehead.

Referenced by ExecMemoize().

◆ entry_purge_tuples()

static void entry_purge_tuples ( MemoizeState mstate,
MemoizeEntry entry 
)
inlinestatic

Definition at line 343 of file nodeMemoize.c.

345 {
346  MemoizeTuple *tuple = entry->tuplehead;
347  uint64 freed_mem = 0;
348 
349  while (tuple != NULL)
350  {
351  MemoizeTuple *next = tuple->next;
352 
353  freed_mem += CACHE_TUPLE_BYTES(tuple);
354 
355  /* Free memory used for this tuple */
356  pfree(tuple->mintuple);
357  pfree(tuple);
358 
359  tuple = next;
360  }
361 
362  entry->complete = false;
363  entry->tuplehead = NULL;
364 
365  /* Update the memory accounting */
366  mstate->mem_used -= freed_mem;
static int32 next
Definition: blutils.c:221
void pfree(void *pointer)
Definition: mcxt.c:1520

References CACHE_TUPLE_BYTES, MemoizeEntry::complete, MemoizeState::mem_used, MemoizeTuple::mintuple, next, MemoizeTuple::next, pfree(), and MemoizeEntry::tuplehead.

Referenced by ExecMemoize(), and remove_cache_entry().

◆ ExecEndMemoize()

void ExecEndMemoize ( MemoizeState node)

Definition at line 1079 of file nodeMemoize.c.

1081 {
1082 #ifdef USE_ASSERT_CHECKING
1083  /* Validate the memory accounting code is correct in assert builds. */
1084  if (node->hashtable != NULL)
1085  {
1086  int count;
1087  uint64 mem = 0;
1088  memoize_iterator i;
1089  MemoizeEntry *entry;
1090 
1091  memoize_start_iterate(node->hashtable, &i);
1092 
1093  count = 0;
1094  while ((entry = memoize_iterate(node->hashtable, &i)) != NULL)
1095  {
1096  MemoizeTuple *tuple = entry->tuplehead;
1097 
1098  mem += EMPTY_ENTRY_MEMORY_BYTES(entry);
1099  while (tuple != NULL)
1100  {
1101  mem += CACHE_TUPLE_BYTES(tuple);
1102  tuple = tuple->next;
1103  }
1104  count++;
1105  }
1106 
1107  Assert(count == node->hashtable->members);
1108  Assert(mem == node->mem_used);
1109  }
1110 #endif
1111 
1112  /*
1113  * When ending a parallel worker, copy the statistics gathered by the
1114  * worker back into shared memory so that it can be picked up by the main
1115  * process to report in EXPLAIN ANALYZE.
1116  */
1117  if (node->shared_info != NULL && IsParallelWorker())
1118  {
1120 
1121  /* Make mem_peak available for EXPLAIN */
1122  if (node->stats.mem_peak == 0)
1123  node->stats.mem_peak = node->mem_used;
1124 
1125  Assert(ParallelWorkerNumber <= node->shared_info->num_workers);
1127  memcpy(si, &node->stats, sizeof(MemoizeInstrumentation));
1128  }
1129 
1130  /* Remove the cache context */
1132 
1133  /*
1134  * shut down the subplan
1135  */
1136  ExecEndNode(outerPlanState(node));
int ParallelWorkerNumber
Definition: parallel.c:112
void ExecEndNode(PlanState *node)
Definition: execProcnode.c:557
#define outerPlanState(node)
Definition: execnodes.h:1213
#define IsParallelWorker()
Definition: parallel.h:60
int i
Definition: isn.c:73
void MemoryContextDelete(MemoryContext context)
Definition: mcxt.c:454
SharedMemoizeInfo * shared_info
Definition: execnodes.h:2297
MemoizeInstrumentation sinstrument[FLEXIBLE_ARRAY_MEMBER]
Definition: execnodes.h:2258

References Assert, CACHE_TUPLE_BYTES, EMPTY_ENTRY_MEMORY_BYTES, ExecEndNode(), MemoizeState::hashtable, i, IsParallelWorker, MemoizeInstrumentation::mem_peak, MemoizeState::mem_used, MemoryContextDelete(), MemoizeTuple::next, outerPlanState, ParallelWorkerNumber, MemoizeState::shared_info, SharedMemoizeInfo::sinstrument, MemoizeState::stats, MemoizeState::tableContext, and MemoizeEntry::tuplehead.

Referenced by ExecEndNode().

◆ ExecEstimateCacheEntryOverheadBytes()

double ExecEstimateCacheEntryOverheadBytes ( double  ntuples)

Definition at line 1171 of file nodeMemoize.c.

1173 {
1174  return sizeof(MemoizeEntry) + sizeof(MemoizeKey) + sizeof(MemoizeTuple) *
1175  ntuples;

Referenced by cost_memoize_rescan().

◆ ExecInitMemoize()

MemoizeState* ExecInitMemoize ( Memoize node,
EState estate,
int  eflags 
)

Definition at line 951 of file nodeMemoize.c.

953 {
955  Plan *outerNode;
956  int i;
957  int nkeys;
958  Oid *eqfuncoids;
959 
960  /* check for unsupported flags */
961  Assert(!(eflags & (EXEC_FLAG_BACKWARD | EXEC_FLAG_MARK)));
962 
963  mstate->ss.ps.plan = (Plan *) node;
964  mstate->ss.ps.state = estate;
965  mstate->ss.ps.ExecProcNode = ExecMemoize;
966 
967  /*
968  * Miscellaneous initialization
969  *
970  * create expression context for node
971  */
972  ExecAssignExprContext(estate, &mstate->ss.ps);
973 
974  outerNode = outerPlan(node);
975  outerPlanState(mstate) = ExecInitNode(outerNode, estate, eflags);
976 
977  /*
978  * Initialize return slot and type. No need to initialize projection info
979  * because this node doesn't do projections.
980  */
982  mstate->ss.ps.ps_ProjInfo = NULL;
983 
984  /*
985  * Initialize scan slot and type.
986  */
988 
989  /*
990  * Set the state machine to lookup the cache. We won't find anything
991  * until we cache something, but this saves a special case to create the
992  * first entry.
993  */
994  mstate->mstatus = MEMO_CACHE_LOOKUP;
995 
996  mstate->nkeys = nkeys = node->numKeys;
1001  &TTSOpsVirtual);
1002 
1003  mstate->param_exprs = (ExprState **) palloc(nkeys * sizeof(ExprState *));
1004  mstate->collations = node->collations; /* Just point directly to the plan
1005  * data */
1006  mstate->hashfunctions = (FmgrInfo *) palloc(nkeys * sizeof(FmgrInfo));
1007 
1008  eqfuncoids = palloc(nkeys * sizeof(Oid));
1009 
1010  for (i = 0; i < nkeys; i++)
1011  {
1012  Oid hashop = node->hashOperators[i];
1013  Oid left_hashfn;
1014  Oid right_hashfn;
1015  Expr *param_expr = (Expr *) list_nth(node->param_exprs, i);
1016 
1017  if (!get_op_hash_functions(hashop, &left_hashfn, &right_hashfn))
1018  elog(ERROR, "could not find hash function for hash operator %u",
1019  hashop);
1020 
1021  fmgr_info(left_hashfn, &mstate->hashfunctions[i]);
1022 
1023  mstate->param_exprs[i] = ExecInitExpr(param_expr, (PlanState *) mstate);
1024  eqfuncoids[i] = get_opcode(hashop);
1025  }
1026 
1029  &TTSOpsVirtual,
1030  eqfuncoids,
1031  node->collations,
1032  node->param_exprs,
1033  (PlanState *) mstate);
1034 
1035  pfree(eqfuncoids);
1036  mstate->mem_used = 0;
1037 
1038  /* Limit the total memory consumed by the cache to this */
1039  mstate->mem_limit = get_hash_memory_limit();
1040 
1041  /* A memory context dedicated for the cache */
1043  "MemoizeHashTable",
1045 
1046  dlist_init(&mstate->lru_list);
1047  mstate->last_tuple = NULL;
1048  mstate->entry = NULL;
1049 
1050  /*
1051  * Mark if we can assume the cache entry is completed after we get the
1052  * first record for it. Some callers might not call us again after
1053  * getting the first match. e.g. A join operator performing a unique join
1054  * is able to skip to the next outer tuple after getting the first
1055  * matching inner tuple. In this case, the cache entry is complete after
1056  * getting the first tuple. This allows us to mark it as so.
1057  */
1058  mstate->singlerow = node->singlerow;
1059  mstate->keyparamids = node->keyparamids;
1060 
1061  /*
1062  * Record if the cache keys should be compared bit by bit, or logically
1063  * using the type's hash equality operator
1064  */
1065  mstate->binary_mode = node->binary_mode;
1066 
1067  /* Zero the statistics counters */
1068  memset(&mstate->stats, 0, sizeof(MemoizeInstrumentation));
1069 
1070  /*
1071  * Because it may require a large allocation, we delay building of the
1072  * hash table until executor run.
1073  */
1074  mstate->hashtable = NULL;
1075 
1076  return mstate;
ExprState * ExecInitExpr(Expr *node, PlanState *parent)
Definition: execExpr.c:134
ExprState * ExecBuildParamSetEqual(TupleDesc desc, const TupleTableSlotOps *lops, const TupleTableSlotOps *rops, const Oid *eqfunctions, const Oid *collations, const List *param_exprs, PlanState *parent)
Definition: execExpr.c:4103
PlanState * ExecInitNode(Plan *node, EState *estate, int eflags)
Definition: execProcnode.c:142
const TupleTableSlotOps TTSOpsVirtual
Definition: execTuples.c:84
void ExecInitResultTupleSlotTL(PlanState *planstate, const TupleTableSlotOps *tts_ops)
Definition: execTuples.c:1886
const TupleTableSlotOps TTSOpsMinimalTuple
Definition: execTuples.c:86
TupleDesc ExecTypeFromExprList(List *exprList)
Definition: execTuples.c:2084
TupleTableSlot * MakeSingleTupleTableSlot(TupleDesc tupdesc, const TupleTableSlotOps *tts_ops)
Definition: execTuples.c:1325
void ExecCreateScanSlotFromOuterPlan(EState *estate, ScanState *scanstate, const TupleTableSlotOps *tts_ops)
Definition: execUtils.c:659
void ExecAssignExprContext(EState *estate, PlanState *planstate)
Definition: execUtils.c:483
#define EXEC_FLAG_BACKWARD
Definition: executor.h:68
#define EXEC_FLAG_MARK
Definition: executor.h:69
void fmgr_info(Oid functionId, FmgrInfo *finfo)
Definition: fmgr.c:127
RegProcedure get_opcode(Oid opno)
Definition: lsyscache.c:1285
bool get_op_hash_functions(Oid opno, RegProcedure *lhs_procno, RegProcedure *rhs_procno)
Definition: lsyscache.c:510
MemoryContext CurrentMemoryContext
Definition: mcxt.c:143
#define AllocSetContextCreate
Definition: memutils.h:129
#define ALLOCSET_DEFAULT_SIZES
Definition: memutils.h:160
size_t get_hash_memory_limit(void)
Definition: nodeHash.c:3595
#define MEMO_CACHE_LOOKUP
Definition: nodeMemoize.c:78
static TupleTableSlot * ExecMemoize(PlanState *pstate)
Definition: nodeMemoize.c:696
#define makeNode(_type_)
Definition: nodes.h:155
static void * list_nth(const List *list, int n)
Definition: pg_list.h:299
#define outerPlan(node)
Definition: plannodes.h:182
unsigned int Oid
Definition: postgres_ext.h:31
Definition: fmgr.h:57
TupleDesc hashkeydesc
Definition: execnodes.h:2274
FmgrInfo * hashfunctions
Definition: execnodes.h:2280
Oid * collations
Definition: execnodes.h:2281
ExprState * cache_eq_expr
Definition: execnodes.h:2277
bool singlerow
Definition: execnodes.h:2292
bool binary_mode
Definition: execnodes.h:2294
Bitmapset * keyparamids
Definition: execnodes.h:2298
ScanState ss
Definition: execnodes.h:2270
ExprState ** param_exprs
Definition: execnodes.h:2278
TupleTableSlot * tableslot
Definition: execnodes.h:2275
bool singlerow
Definition: plannodes.h:909
Bitmapset * keyparamids
Definition: plannodes.h:924
bool binary_mode
Definition: plannodes.h:915
int numKeys
Definition: plannodes.h:894
List * param_exprs
Definition: plannodes.h:903
Plan * plan
Definition: execnodes.h:1117
EState * state
Definition: execnodes.h:1119
ProjectionInfo * ps_ProjInfo
Definition: execnodes.h:1157
ExecProcNodeMtd ExecProcNode
Definition: execnodes.h:1123
PlanState ps
Definition: execnodes.h:1564

References ALLOCSET_DEFAULT_SIZES, AllocSetContextCreate, Assert, MemoizeState::binary_mode, Memoize::binary_mode, MemoizeState::cache_eq_expr, MemoizeState::collations, CurrentMemoryContext, dlist_init(), elog, MemoizeState::entry, ERROR, EXEC_FLAG_BACKWARD, EXEC_FLAG_MARK, ExecAssignExprContext(), ExecBuildParamSetEqual(), ExecCreateScanSlotFromOuterPlan(), ExecInitExpr(), ExecInitNode(), ExecInitResultTupleSlotTL(), ExecMemoize(), PlanState::ExecProcNode, ExecTypeFromExprList(), fmgr_info(), get_hash_memory_limit(), get_op_hash_functions(), get_opcode(), MemoizeState::hashfunctions, MemoizeState::hashkeydesc, MemoizeState::hashtable, i, MemoizeState::keyparamids, Memoize::keyparamids, MemoizeState::last_tuple, list_nth(), MemoizeState::lru_list, makeNode, MakeSingleTupleTableSlot(), MemoizeState::mem_limit, MemoizeState::mem_used, MEMO_CACHE_LOOKUP, MemoizeState::mstatus, MemoizeState::nkeys, Memoize::numKeys, outerPlan, outerPlanState, palloc(), MemoizeState::param_exprs, Memoize::param_exprs, pfree(), PlanState::plan, MemoizeState::probeslot, ScanState::ps, PlanState::ps_ProjInfo, MemoizeState::singlerow, Memoize::singlerow, MemoizeState::ss, PlanState::state, MemoizeState::stats, MemoizeState::tableContext, MemoizeState::tableslot, TTSOpsMinimalTuple, and TTSOpsVirtual.

Referenced by ExecInitNode().

◆ ExecMemoize()

static TupleTableSlot* ExecMemoize ( PlanState pstate)
static

Definition at line 696 of file nodeMemoize.c.

698 {
699  MemoizeState *node = castNode(MemoizeState, pstate);
700  ExprContext *econtext = node->ss.ps.ps_ExprContext;
701  PlanState *outerNode;
702  TupleTableSlot *slot;
703 
705 
706  /*
707  * Reset per-tuple memory context to free any expression evaluation
708  * storage allocated in the previous tuple cycle.
709  */
710  ResetExprContext(econtext);
711 
712  switch (node->mstatus)
713  {
714  case MEMO_CACHE_LOOKUP:
715  {
716  MemoizeEntry *entry;
717  TupleTableSlot *outerslot;
718  bool found;
719 
720  Assert(node->entry == NULL);
721 
722  /* first call? we'll need a hash table. */
723  if (unlikely(node->hashtable == NULL))
724  build_hash_table(node, ((Memoize *) pstate->plan)->est_entries);
725 
726  /*
727  * We're only ever in this state for the first call of the
728  * scan. Here we have a look to see if we've already seen the
729  * current parameters before and if we have already cached a
730  * complete set of records that the outer plan will return for
731  * these parameters.
732  *
733  * When we find a valid cache entry, we'll return the first
734  * tuple from it. If not found, we'll create a cache entry and
735  * then try to fetch a tuple from the outer scan. If we find
736  * one there, we'll try to cache it.
737  */
738 
739  /* see if we've got anything cached for the current parameters */
740  entry = cache_lookup(node, &found);
741 
742  if (found && entry->complete)
743  {
744  node->stats.cache_hits += 1; /* stats update */
745 
746  /*
747  * Set last_tuple and entry so that the state
748  * MEMO_CACHE_FETCH_NEXT_TUPLE can easily find the next
749  * tuple for these parameters.
750  */
751  node->last_tuple = entry->tuplehead;
752  node->entry = entry;
753 
754  /* Fetch the first cached tuple, if there is one */
755  if (entry->tuplehead)
756  {
758 
759  slot = node->ss.ps.ps_ResultTupleSlot;
761  slot, false);
762 
763  return slot;
764  }
765 
766  /* The cache entry is void of any tuples. */
767  node->mstatus = MEMO_END_OF_SCAN;
768  return NULL;
769  }
770 
771  /* Handle cache miss */
772  node->stats.cache_misses += 1; /* stats update */
773 
774  if (found)
775  {
776  /*
777  * A cache entry was found, but the scan for that entry
778  * did not run to completion. We'll just remove all
779  * tuples and start again. It might be tempting to
780  * continue where we left off, but there's no guarantee
781  * the outer node will produce the tuples in the same
782  * order as it did last time.
783  */
784  entry_purge_tuples(node, entry);
785  }
786 
787  /* Scan the outer node for a tuple to cache */
788  outerNode = outerPlanState(node);
789  outerslot = ExecProcNode(outerNode);
790  if (TupIsNull(outerslot))
791  {
792  /*
793  * cache_lookup may have returned NULL due to failure to
794  * free enough cache space, so ensure we don't do anything
795  * here that assumes it worked. There's no need to go into
796  * bypass mode here as we're setting mstatus to end of
797  * scan.
798  */
799  if (likely(entry))
800  entry->complete = true;
801 
802  node->mstatus = MEMO_END_OF_SCAN;
803  return NULL;
804  }
805 
806  node->entry = entry;
807 
808  /*
809  * If we failed to create the entry or failed to store the
810  * tuple in the entry, then go into bypass mode.
811  */
812  if (unlikely(entry == NULL ||
813  !cache_store_tuple(node, outerslot)))
814  {
815  node->stats.cache_overflows += 1; /* stats update */
816 
818 
819  /*
820  * No need to clear out last_tuple as we'll stay in bypass
821  * mode until the end of the scan.
822  */
823  }
824  else
825  {
826  /*
827  * If we only expect a single row from this scan then we
828  * can mark that we're not expecting more. This allows
829  * cache lookups to work even when the scan has not been
830  * executed to completion.
831  */
832  entry->complete = node->singlerow;
833  node->mstatus = MEMO_FILLING_CACHE;
834  }
835 
836  slot = node->ss.ps.ps_ResultTupleSlot;
837  ExecCopySlot(slot, outerslot);
838  return slot;
839  }
840 
842  {
843  /* We shouldn't be in this state if these are not set */
844  Assert(node->entry != NULL);
845  Assert(node->last_tuple != NULL);
846 
847  /* Skip to the next tuple to output */
848  node->last_tuple = node->last_tuple->next;
849 
850  /* No more tuples in the cache */
851  if (node->last_tuple == NULL)
852  {
853  node->mstatus = MEMO_END_OF_SCAN;
854  return NULL;
855  }
856 
857  slot = node->ss.ps.ps_ResultTupleSlot;
859  false);
860 
861  return slot;
862  }
863 
864  case MEMO_FILLING_CACHE:
865  {
866  TupleTableSlot *outerslot;
867  MemoizeEntry *entry = node->entry;
868 
869  /* entry should already have been set by MEMO_CACHE_LOOKUP */
870  Assert(entry != NULL);
871 
872  /*
873  * When in the MEMO_FILLING_CACHE state, we've just had a
874  * cache miss and are populating the cache with the current
875  * scan tuples.
876  */
877  outerNode = outerPlanState(node);
878  outerslot = ExecProcNode(outerNode);
879  if (TupIsNull(outerslot))
880  {
881  /* No more tuples. Mark it as complete */
882  entry->complete = true;
883  node->mstatus = MEMO_END_OF_SCAN;
884  return NULL;
885  }
886 
887  /*
888  * Validate if the planner properly set the singlerow flag. It
889  * should only set that if each cache entry can, at most,
890  * return 1 row.
891  */
892  if (unlikely(entry->complete))
893  elog(ERROR, "cache entry already complete");
894 
895  /* Record the tuple in the current cache entry */
896  if (unlikely(!cache_store_tuple(node, outerslot)))
897  {
898  /* Couldn't store it? Handle overflow */
899  node->stats.cache_overflows += 1; /* stats update */
900 
902 
903  /*
904  * No need to clear out entry or last_tuple as we'll stay
905  * in bypass mode until the end of the scan.
906  */
907  }
908 
909  slot = node->ss.ps.ps_ResultTupleSlot;
910  ExecCopySlot(slot, outerslot);
911  return slot;
912  }
913 
915  {
916  TupleTableSlot *outerslot;
917 
918  /*
919  * When in bypass mode we just continue to read tuples without
920  * caching. We need to wait until the next rescan before we
921  * can come out of this mode.
922  */
923  outerNode = outerPlanState(node);
924  outerslot = ExecProcNode(outerNode);
925  if (TupIsNull(outerslot))
926  {
927  node->mstatus = MEMO_END_OF_SCAN;
928  return NULL;
929  }
930 
931  slot = node->ss.ps.ps_ResultTupleSlot;
932  ExecCopySlot(slot, outerslot);
933  return slot;
934  }
935 
936  case MEMO_END_OF_SCAN:
937 
938  /*
939  * We've already returned NULL for this scan, but just in case
940  * something calls us again by mistake.
941  */
942  return NULL;
943 
944  default:
945  elog(ERROR, "unrecognized memoize state: %d",
946  (int) node->mstatus);
947  return NULL;
948  } /* switch */
#define likely(x)
Definition: c.h:310
TupleTableSlot * ExecStoreMinimalTuple(MinimalTuple mtup, TupleTableSlot *slot, bool shouldFree)
Definition: execTuples.c:1533
#define ResetExprContext(econtext)
Definition: executor.h:544
static TupleTableSlot * ExecProcNode(PlanState *node)
Definition: executor.h:269
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
#define MEMO_CACHE_FETCH_NEXT_TUPLE
Definition: nodeMemoize.c:79
static bool cache_store_tuple(MemoizeState *mstate, TupleTableSlot *slot)
Definition: nodeMemoize.c:624
#define MEMO_CACHE_BYPASS_MODE
Definition: nodeMemoize.c:81
#define MEMO_END_OF_SCAN
Definition: nodeMemoize.c:82
#define MEMO_FILLING_CACHE
Definition: nodeMemoize.c:80
static MemoizeEntry * cache_lookup(MemoizeState *mstate, bool *found)
Definition: nodeMemoize.c:527
static void entry_purge_tuples(MemoizeState *mstate, MemoizeEntry *entry)
Definition: nodeMemoize.c:343
static void build_hash_table(MemoizeState *mstate, uint32 size)
Definition: nodeMemoize.c:282
#define castNode(_type_, nodeptr)
Definition: nodes.h:176
ExprContext * ps_ExprContext
Definition: execnodes.h:1156
TupleTableSlot * ps_ResultTupleSlot
Definition: execnodes.h:1155
static TupleTableSlot * ExecCopySlot(TupleTableSlot *dstslot, TupleTableSlot *srcslot)
Definition: tuptable.h:509
#define TupIsNull(slot)
Definition: tuptable.h:306

References Assert, build_hash_table(), MemoizeInstrumentation::cache_hits, cache_lookup(), MemoizeInstrumentation::cache_misses, MemoizeInstrumentation::cache_overflows, cache_store_tuple(), castNode, CHECK_FOR_INTERRUPTS, MemoizeEntry::complete, elog, MemoizeState::entry, entry_purge_tuples(), ERROR, ExecCopySlot(), ExecProcNode(), ExecStoreMinimalTuple(), MemoizeState::hashtable, MemoizeState::last_tuple, likely, MEMO_CACHE_BYPASS_MODE, MEMO_CACHE_FETCH_NEXT_TUPLE, MEMO_CACHE_LOOKUP, MEMO_END_OF_SCAN, MEMO_FILLING_CACHE, MemoizeTuple::mintuple, MemoizeState::mstatus, MemoizeTuple::next, outerPlanState, PlanState::plan, ScanState::ps, PlanState::ps_ExprContext, PlanState::ps_ResultTupleSlot, ResetExprContext, MemoizeState::singlerow, MemoizeState::ss, MemoizeState::stats, TupIsNull, MemoizeEntry::tuplehead, and unlikely.

Referenced by ExecInitMemoize().

◆ ExecMemoizeEstimate()

void ExecMemoizeEstimate ( MemoizeState node,
ParallelContext pcxt 
)

Definition at line 1189 of file nodeMemoize.c.

1191 {
1192  Size size;
1193 
1194  /* don't need this if not instrumenting or no workers */
1195  if (!node->ss.ps.instrument || pcxt->nworkers == 0)
1196  return;
1197 
1198  size = mul_size(pcxt->nworkers, sizeof(MemoizeInstrumentation));
1199  size = add_size(size, offsetof(SharedMemoizeInfo, sinstrument));
1201  shm_toc_estimate_keys(&pcxt->estimator, 1);
size_t Size
Definition: c.h:605
#define shm_toc_estimate_chunk(e, sz)
Definition: shm_toc.h:51
#define shm_toc_estimate_keys(e, cnt)
Definition: shm_toc.h:53
Size add_size(Size s1, Size s2)
Definition: shmem.c:493
Size mul_size(Size s1, Size s2)
Definition: shmem.c:510
shm_toc_estimator estimator
Definition: parallel.h:41
Instrumentation * instrument
Definition: execnodes.h:1127

References add_size(), ParallelContext::estimator, PlanState::instrument, mul_size(), ParallelContext::nworkers, ScanState::ps, shm_toc_estimate_chunk, shm_toc_estimate_keys, size, and MemoizeState::ss.

Referenced by ExecParallelEstimate().

◆ ExecMemoizeInitializeDSM()

void ExecMemoizeInitializeDSM ( MemoizeState node,
ParallelContext pcxt 
)

Definition at line 1210 of file nodeMemoize.c.

1212 {
1213  Size size;
1214 
1215  /* don't need this if not instrumenting or no workers */
1216  if (!node->ss.ps.instrument || pcxt->nworkers == 0)
1217  return;
1218 
1219  size = offsetof(SharedMemoizeInfo, sinstrument)
1220  + pcxt->nworkers * sizeof(MemoizeInstrumentation);
1221  node->shared_info = shm_toc_allocate(pcxt->toc, size);
1222  /* ensure any unfilled slots will contain zeroes */
1223  memset(node->shared_info, 0, size);
1224  node->shared_info->num_workers = pcxt->nworkers;
1225  shm_toc_insert(pcxt->toc, node->ss.ps.plan->plan_node_id,
1226  node->shared_info);
struct MemoizeInstrumentation MemoizeInstrumentation
void shm_toc_insert(shm_toc *toc, uint64 key, void *address)
Definition: shm_toc.c:171
void * shm_toc_allocate(shm_toc *toc, Size nbytes)
Definition: shm_toc.c:88
shm_toc * toc
Definition: parallel.h:44
int plan_node_id
Definition: plannodes.h:151

References PlanState::instrument, SharedMemoizeInfo::num_workers, ParallelContext::nworkers, PlanState::plan, Plan::plan_node_id, ScanState::ps, MemoizeState::shared_info, shm_toc_allocate(), shm_toc_insert(), size, MemoizeState::ss, and ParallelContext::toc.

Referenced by ExecParallelInitializeDSM().

◆ ExecMemoizeInitializeWorker()

void ExecMemoizeInitializeWorker ( MemoizeState node,
ParallelWorkerContext pwcxt 
)

Definition at line 1235 of file nodeMemoize.c.

1237 {
1238  node->shared_info =
1239  shm_toc_lookup(pwcxt->toc, node->ss.ps.plan->plan_node_id, true);
void * shm_toc_lookup(shm_toc *toc, uint64 key, bool noError)
Definition: shm_toc.c:232

References PlanState::plan, Plan::plan_node_id, ScanState::ps, MemoizeState::shared_info, shm_toc_lookup(), MemoizeState::ss, and ParallelWorkerContext::toc.

Referenced by ExecParallelInitializeWorker().

◆ ExecMemoizeRetrieveInstrumentation()

void ExecMemoizeRetrieveInstrumentation ( MemoizeState node)

Definition at line 1248 of file nodeMemoize.c.

1250 {
1251  Size size;
1252  SharedMemoizeInfo *si;
1253 
1254  if (node->shared_info == NULL)
1255  return;
1256 
1257  size = offsetof(SharedMemoizeInfo, sinstrument)
1258  + node->shared_info->num_workers * sizeof(MemoizeInstrumentation);
1259  si = palloc(size);
1260  memcpy(si, node->shared_info, size);
1261  node->shared_info = si;

References SharedMemoizeInfo::num_workers, palloc(), MemoizeState::shared_info, and size.

Referenced by ExecParallelRetrieveInstrumentation().

◆ ExecReScanMemoize()

void ExecReScanMemoize ( MemoizeState node)

Definition at line 1139 of file nodeMemoize.c.

1141 {
1143 
1144  /* Mark that we must lookup the cache for a new set of parameters */
1145  node->mstatus = MEMO_CACHE_LOOKUP;
1146 
1147  /* nullify pointers used for the last scan */
1148  node->entry = NULL;
1149  node->last_tuple = NULL;
1150 
1151  /*
1152  * if chgParam of subnode is not null then plan will be re-scanned by
1153  * first ExecProcNode.
1154  */
1155  if (outerPlan->chgParam == NULL)
1157 
1158  /*
1159  * Purge the entire cache if a parameter changed that is not part of the
1160  * cache key.
1161  */
1162  if (bms_nonempty_difference(outerPlan->chgParam, node->keyparamids))
1163  cache_purge_all(node);
bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b)
Definition: bitmapset.c:641
void ExecReScan(PlanState *node)
Definition: execAmi.c:76
static void cache_purge_all(MemoizeState *mstate)
Definition: nodeMemoize.c:401

References bms_nonempty_difference(), cache_purge_all(), MemoizeState::entry, ExecReScan(), MemoizeState::keyparamids, MemoizeState::last_tuple, MEMO_CACHE_LOOKUP, MemoizeState::mstatus, outerPlan, and outerPlanState.

Referenced by ExecReScan().

◆ MemoizeHash_equal()

static bool MemoizeHash_equal ( struct memoize_hash *  tb,
const MemoizeKey key1,
const MemoizeKey key2 
)
static

Definition at line 220 of file nodeMemoize.c.

223 {
224  MemoizeState *mstate = (MemoizeState *) tb->private_data;
225  ExprContext *econtext = mstate->ss.ps.ps_ExprContext;
226  TupleTableSlot *tslot = mstate->tableslot;
227  TupleTableSlot *pslot = mstate->probeslot;
228 
229  /* probeslot should have already been prepared by prepare_probe_slot() */
230  ExecStoreMinimalTuple(key1->params, tslot, false);
231 
232  if (mstate->binary_mode)
233  {
234  MemoryContext oldcontext;
235  int numkeys = mstate->nkeys;
236  bool match = true;
237 
238  oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
239 
240  slot_getallattrs(tslot);
241  slot_getallattrs(pslot);
242 
243  for (int i = 0; i < numkeys; i++)
244  {
245  FormData_pg_attribute *attr;
246 
247  if (tslot->tts_isnull[i] != pslot->tts_isnull[i])
248  {
249  match = false;
250  break;
251  }
252 
253  /* both NULL? they're equal */
254  if (tslot->tts_isnull[i])
255  continue;
256 
257  /* perform binary comparison on the two datums */
258  attr = &tslot->tts_tupleDescriptor->attrs[i];
259  if (!datum_image_eq(tslot->tts_values[i], pslot->tts_values[i],
260  attr->attbyval, attr->attlen))
261  {
262  match = false;
263  break;
264  }
265  }
266 
267  MemoryContextSwitchTo(oldcontext);
268  return match;
269  }
270  else
271  {
272  econtext->ecxt_innertuple = tslot;
273  econtext->ecxt_outertuple = pslot;
274  return ExecQual(mstate->cache_eq_expr, econtext);
275  }
bool datum_image_eq(Datum value1, Datum value2, bool typByVal, int typLen)
Definition: datum.c:266
static bool ExecQual(ExprState *state, ExprContext *econtext)
Definition: executor.h:413
FormData_pg_attribute
Definition: pg_attribute.h:193
MinimalTuple params
Definition: nodeMemoize.c:106
static void slot_getallattrs(TupleTableSlot *slot)
Definition: tuptable.h:368

References MemoizeState::binary_mode, MemoizeState::cache_eq_expr, datum_image_eq(), ExecQual(), ExecStoreMinimalTuple(), FormData_pg_attribute, i, MemoryContextSwitchTo(), MemoizeState::nkeys, MemoizeKey::params, MemoizeState::probeslot, ScanState::ps, PlanState::ps_ExprContext, slot_getallattrs(), MemoizeState::ss, and MemoizeState::tableslot.

◆ MemoizeHash_hash()

static uint32 MemoizeHash_hash ( struct memoize_hash *  tb,
const MemoizeKey key 
)
static

Definition at line 157 of file nodeMemoize.c.

159 {
160  MemoizeState *mstate = (MemoizeState *) tb->private_data;
161  ExprContext *econtext = mstate->ss.ps.ps_ExprContext;
162  MemoryContext oldcontext;
163  TupleTableSlot *pslot = mstate->probeslot;
164  uint32 hashkey = 0;
165  int numkeys = mstate->nkeys;
166 
167  oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
168 
169  if (mstate->binary_mode)
170  {
171  for (int i = 0; i < numkeys; i++)
172  {
173  /* combine successive hashkeys by rotating */
174  hashkey = pg_rotate_left32(hashkey, 1);
175 
176  if (!pslot->tts_isnull[i]) /* treat nulls as having hash key 0 */
177  {
178  FormData_pg_attribute *attr;
179  uint32 hkey;
180 
181  attr = &pslot->tts_tupleDescriptor->attrs[i];
182 
183  hkey = datum_image_hash(pslot->tts_values[i], attr->attbyval, attr->attlen);
184 
185  hashkey ^= hkey;
186  }
187  }
188  }
189  else
190  {
191  FmgrInfo *hashfunctions = mstate->hashfunctions;
192  Oid *collations = mstate->collations;
193 
194  for (int i = 0; i < numkeys; i++)
195  {
196  /* combine successive hashkeys by rotating */
197  hashkey = pg_rotate_left32(hashkey, 1);
198 
199  if (!pslot->tts_isnull[i]) /* treat nulls as having hash key 0 */
200  {
201  uint32 hkey;
202 
203  hkey = DatumGetUInt32(FunctionCall1Coll(&hashfunctions[i],
204  collations[i], pslot->tts_values[i]));
205  hashkey ^= hkey;
206  }
207  }
208  }
209 
210  MemoryContextSwitchTo(oldcontext);
211  return murmurhash32(hashkey);
unsigned int uint32
Definition: c.h:506
uint32 datum_image_hash(Datum value, bool typByVal, int typLen)
Definition: datum.c:338
Datum FunctionCall1Coll(FmgrInfo *flinfo, Oid collation, Datum arg1)
Definition: fmgr.c:1129
static uint32 murmurhash32(uint32 data)
Definition: hashfn.h:92
static uint32 pg_rotate_left32(uint32 word, int n)
Definition: pg_bitutils.h:404
static uint32 DatumGetUInt32(Datum X)
Definition: postgres.h:222

References MemoizeState::binary_mode, MemoizeState::collations, datum_image_hash(), DatumGetUInt32(), FormData_pg_attribute, FunctionCall1Coll(), MemoizeState::hashfunctions, i, MemoryContextSwitchTo(), murmurhash32(), MemoizeState::nkeys, pg_rotate_left32(), MemoizeState::probeslot, ScanState::ps, PlanState::ps_ExprContext, and MemoizeState::ss.

◆ prepare_probe_slot()

static void prepare_probe_slot ( MemoizeState mstate,
MemoizeKey key 
)
inlinestatic

Definition at line 301 of file nodeMemoize.c.

303 {
304  TupleTableSlot *pslot = mstate->probeslot;
305  TupleTableSlot *tslot = mstate->tableslot;
306  int numKeys = mstate->nkeys;
307 
308  ExecClearTuple(pslot);
309 
310  if (key == NULL)
311  {
312  ExprContext *econtext = mstate->ss.ps.ps_ExprContext;
313  MemoryContext oldcontext;
314 
315  oldcontext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
316 
317  /* Set the probeslot's values based on the current parameter values */
318  for (int i = 0; i < numKeys; i++)
319  pslot->tts_values[i] = ExecEvalExpr(mstate->param_exprs[i],
320  econtext,
321  &pslot->tts_isnull[i]);
322 
323  MemoryContextSwitchTo(oldcontext);
324  }
325  else
326  {
327  /* Process the key's MinimalTuple and store the values in probeslot */
328  ExecStoreMinimalTuple(key->params, tslot, false);
329  slot_getallattrs(tslot);
330  memcpy(pslot->tts_values, tslot->tts_values, sizeof(Datum) * numKeys);
331  memcpy(pslot->tts_isnull, tslot->tts_isnull, sizeof(bool) * numKeys);
332  }
333 
334  ExecStoreVirtualTuple(pslot);
TupleTableSlot * ExecStoreVirtualTuple(TupleTableSlot *slot)
Definition: execTuples.c:1639
static Datum ExecEvalExpr(ExprState *state, ExprContext *econtext, bool *isNull)
Definition: executor.h:333
uintptr_t Datum
Definition: postgres.h:64
MemoryContext ecxt_per_tuple_memory
Definition: execnodes.h:263
bool * tts_isnull
Definition: tuptable.h:127
Datum * tts_values
Definition: tuptable.h:125
static TupleTableSlot * ExecClearTuple(TupleTableSlot *slot)
Definition: tuptable.h:454

References ExprContext::ecxt_per_tuple_memory, ExecClearTuple(), ExecEvalExpr(), ExecStoreMinimalTuple(), ExecStoreVirtualTuple(), i, sort-test::key, MemoryContextSwitchTo(), MemoizeState::nkeys, MemoizeState::param_exprs, MemoizeState::probeslot, ScanState::ps, PlanState::ps_ExprContext, slot_getallattrs(), MemoizeState::ss, MemoizeState::tableslot, TupleTableSlot::tts_isnull, and TupleTableSlot::tts_values.

Referenced by cache_lookup(), cache_reduce_memory(), and cache_store_tuple().

◆ remove_cache_entry()

static void remove_cache_entry ( MemoizeState mstate,
MemoizeEntry entry 
)
static

Definition at line 373 of file nodeMemoize.c.

375 {
376  MemoizeKey *key = entry->key;
377 
378  dlist_delete(&entry->key->lru_node);
379 
380  /* Remove all of the tuples from this entry */
381  entry_purge_tuples(mstate, entry);
382 
383  /*
384  * Update memory accounting. entry_purge_tuples should have already
385  * subtracted the memory used for each cached tuple. Here we just update
386  * the amount used by the entry itself.
387  */
388  mstate->mem_used -= EMPTY_ENTRY_MEMORY_BYTES(entry);
389 
390  /* Remove the entry from the cache */
391  memoize_delete_item(mstate->hashtable, entry);
392 
393  pfree(key->params);
394  pfree(key);
static void dlist_delete(dlist_node *node)
Definition: ilist.h:405

References dlist_delete(), EMPTY_ENTRY_MEMORY_BYTES, entry_purge_tuples(), MemoizeState::hashtable, MemoizeEntry::key, sort-test::key, MemoizeKey::lru_node, MemoizeState::mem_used, and pfree().

Referenced by cache_reduce_memory().