PostgreSQL Source Code  git master
execParallel.h File Reference
#include "access/parallel.h"
#include "nodes/execnodes.h"
#include "nodes/parsenodes.h"
#include "nodes/plannodes.h"
#include "utils/dsa.h"
Include dependency graph for execParallel.h:
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Data Structures

struct  ParallelExecutorInfo
 

Typedefs

typedef struct SharedExecutorInstrumentation SharedExecutorInstrumentation
 
typedef struct ParallelExecutorInfo ParallelExecutorInfo
 

Functions

ParallelExecutorInfoExecInitParallelPlan (PlanState *planstate, EState *estate, Bitmapset *sendParams, int nworkers, int64 tuples_needed)
 
void ExecParallelCreateReaders (ParallelExecutorInfo *pei)
 
void ExecParallelFinish (ParallelExecutorInfo *pei)
 
void ExecParallelCleanup (ParallelExecutorInfo *pei)
 
void ExecParallelReinitialize (PlanState *planstate, ParallelExecutorInfo *pei, Bitmapset *sendParams)
 
void ParallelQueryMain (dsm_segment *seg, shm_toc *toc)
 

Typedef Documentation

◆ ParallelExecutorInfo

◆ SharedExecutorInstrumentation

Function Documentation

◆ ExecInitParallelPlan()

ParallelExecutorInfo* ExecInitParallelPlan ( PlanState planstate,
EState estate,
Bitmapset sendParams,
int  nworkers,
int64  tuples_needed 
)

Definition at line 587 of file execParallel.c.

590 {
592  ParallelContext *pcxt;
596  char *pstmt_data;
597  char *pstmt_space;
598  char *paramlistinfo_space;
599  BufferUsage *bufusage_space;
600  WalUsage *walusage_space;
601  SharedExecutorInstrumentation *instrumentation = NULL;
602  SharedJitInstrumentation *jit_instrumentation = NULL;
603  int pstmt_len;
604  int paramlistinfo_len;
605  int instrumentation_len = 0;
606  int jit_instrumentation_len = 0;
607  int instrument_offset = 0;
608  Size dsa_minsize = dsa_minimum_size();
609  char *query_string;
610  int query_len;
611 
612  /*
613  * Force any initplan outputs that we're going to pass to workers to be
614  * evaluated, if they weren't already.
615  *
616  * For simplicity, we use the EState's per-output-tuple ExprContext here.
617  * That risks intra-query memory leakage, since we might pass through here
618  * many times before that ExprContext gets reset; but ExecSetParamPlan
619  * doesn't normally leak any memory in the context (see its comments), so
620  * it doesn't seem worth complicating this function's API to pass it a
621  * shorter-lived ExprContext. This might need to change someday.
622  */
623  ExecSetParamPlanMulti(sendParams, GetPerTupleExprContext(estate));
624 
625  /* Allocate object for return value. */
626  pei = palloc0(sizeof(ParallelExecutorInfo));
627  pei->finished = false;
628  pei->planstate = planstate;
629 
630  /* Fix up and serialize plan to be sent to workers. */
631  pstmt_data = ExecSerializePlan(planstate->plan, estate);
632 
633  /* Create a parallel context. */
634  pcxt = CreateParallelContext("postgres", "ParallelQueryMain", nworkers);
635  pei->pcxt = pcxt;
636 
637  /*
638  * Before telling the parallel context to create a dynamic shared memory
639  * segment, we need to figure out how big it should be. Estimate space
640  * for the various things we need to store.
641  */
642 
643  /* Estimate space for fixed-size state. */
646  shm_toc_estimate_keys(&pcxt->estimator, 1);
647 
648  /* Estimate space for query text. */
649  query_len = strlen(estate->es_sourceText);
650  shm_toc_estimate_chunk(&pcxt->estimator, query_len + 1);
651  shm_toc_estimate_keys(&pcxt->estimator, 1);
652 
653  /* Estimate space for serialized PlannedStmt. */
654  pstmt_len = strlen(pstmt_data) + 1;
655  shm_toc_estimate_chunk(&pcxt->estimator, pstmt_len);
656  shm_toc_estimate_keys(&pcxt->estimator, 1);
657 
658  /* Estimate space for serialized ParamListInfo. */
659  paramlistinfo_len = EstimateParamListSpace(estate->es_param_list_info);
660  shm_toc_estimate_chunk(&pcxt->estimator, paramlistinfo_len);
661  shm_toc_estimate_keys(&pcxt->estimator, 1);
662 
663  /*
664  * Estimate space for BufferUsage.
665  *
666  * If EXPLAIN is not in use and there are no extensions loaded that care,
667  * we could skip this. But we have no way of knowing whether anyone's
668  * looking at pgBufferUsage, so do it unconditionally.
669  */
671  mul_size(sizeof(BufferUsage), pcxt->nworkers));
672  shm_toc_estimate_keys(&pcxt->estimator, 1);
673 
674  /*
675  * Same thing for WalUsage.
676  */
678  mul_size(sizeof(WalUsage), pcxt->nworkers));
679  shm_toc_estimate_keys(&pcxt->estimator, 1);
680 
681  /* Estimate space for tuple queues. */
684  shm_toc_estimate_keys(&pcxt->estimator, 1);
685 
686  /*
687  * Give parallel-aware nodes a chance to add to the estimates, and get a
688  * count of how many PlanState nodes there are.
689  */
690  e.pcxt = pcxt;
691  e.nnodes = 0;
692  ExecParallelEstimate(planstate, &e);
693 
694  /* Estimate space for instrumentation, if required. */
695  if (estate->es_instrument)
696  {
697  instrumentation_len =
698  offsetof(SharedExecutorInstrumentation, plan_node_id) +
699  sizeof(int) * e.nnodes;
700  instrumentation_len = MAXALIGN(instrumentation_len);
701  instrument_offset = instrumentation_len;
702  instrumentation_len +=
703  mul_size(sizeof(Instrumentation),
704  mul_size(e.nnodes, nworkers));
705  shm_toc_estimate_chunk(&pcxt->estimator, instrumentation_len);
706  shm_toc_estimate_keys(&pcxt->estimator, 1);
707 
708  /* Estimate space for JIT instrumentation, if required. */
709  if (estate->es_jit_flags != PGJIT_NONE)
710  {
711  jit_instrumentation_len =
712  offsetof(SharedJitInstrumentation, jit_instr) +
713  sizeof(JitInstrumentation) * nworkers;
714  shm_toc_estimate_chunk(&pcxt->estimator, jit_instrumentation_len);
715  shm_toc_estimate_keys(&pcxt->estimator, 1);
716  }
717  }
718 
719  /* Estimate space for DSA area. */
720  shm_toc_estimate_chunk(&pcxt->estimator, dsa_minsize);
721  shm_toc_estimate_keys(&pcxt->estimator, 1);
722 
723  /*
724  * InitializeParallelDSM() passes the active snapshot to the parallel
725  * worker, which uses it to set es_snapshot. Make sure we don't set
726  * es_snapshot differently in the child.
727  */
728  Assert(GetActiveSnapshot() == estate->es_snapshot);
729 
730  /* Everyone's had a chance to ask for space, so now create the DSM. */
731  InitializeParallelDSM(pcxt);
732 
733  /*
734  * OK, now we have a dynamic shared memory segment, and it should be big
735  * enough to store all of the data we estimated we would want to put into
736  * it, plus whatever general stuff (not specifically executor-related) the
737  * ParallelContext itself needs to store there. None of the space we
738  * asked for has been allocated or initialized yet, though, so do that.
739  */
740 
741  /* Store fixed-size state. */
742  fpes = shm_toc_allocate(pcxt->toc, sizeof(FixedParallelExecutorState));
743  fpes->tuples_needed = tuples_needed;
745  fpes->eflags = estate->es_top_eflags;
746  fpes->jit_flags = estate->es_jit_flags;
748 
749  /* Store query string */
750  query_string = shm_toc_allocate(pcxt->toc, query_len + 1);
751  memcpy(query_string, estate->es_sourceText, query_len + 1);
752  shm_toc_insert(pcxt->toc, PARALLEL_KEY_QUERY_TEXT, query_string);
753 
754  /* Store serialized PlannedStmt. */
755  pstmt_space = shm_toc_allocate(pcxt->toc, pstmt_len);
756  memcpy(pstmt_space, pstmt_data, pstmt_len);
757  shm_toc_insert(pcxt->toc, PARALLEL_KEY_PLANNEDSTMT, pstmt_space);
758 
759  /* Store serialized ParamListInfo. */
760  paramlistinfo_space = shm_toc_allocate(pcxt->toc, paramlistinfo_len);
761  shm_toc_insert(pcxt->toc, PARALLEL_KEY_PARAMLISTINFO, paramlistinfo_space);
762  SerializeParamList(estate->es_param_list_info, &paramlistinfo_space);
763 
764  /* Allocate space for each worker's BufferUsage; no need to initialize. */
765  bufusage_space = shm_toc_allocate(pcxt->toc,
766  mul_size(sizeof(BufferUsage), pcxt->nworkers));
767  shm_toc_insert(pcxt->toc, PARALLEL_KEY_BUFFER_USAGE, bufusage_space);
768  pei->buffer_usage = bufusage_space;
769 
770  /* Same for WalUsage. */
771  walusage_space = shm_toc_allocate(pcxt->toc,
772  mul_size(sizeof(WalUsage), pcxt->nworkers));
773  shm_toc_insert(pcxt->toc, PARALLEL_KEY_WAL_USAGE, walusage_space);
774  pei->wal_usage = walusage_space;
775 
776  /* Set up the tuple queues that the workers will write into. */
777  pei->tqueue = ExecParallelSetupTupleQueues(pcxt, false);
778 
779  /* We don't need the TupleQueueReaders yet, though. */
780  pei->reader = NULL;
781 
782  /*
783  * If instrumentation options were supplied, allocate space for the data.
784  * It only gets partially initialized here; the rest happens during
785  * ExecParallelInitializeDSM.
786  */
787  if (estate->es_instrument)
788  {
789  Instrumentation *instrument;
790  int i;
791 
792  instrumentation = shm_toc_allocate(pcxt->toc, instrumentation_len);
793  instrumentation->instrument_options = estate->es_instrument;
794  instrumentation->instrument_offset = instrument_offset;
795  instrumentation->num_workers = nworkers;
796  instrumentation->num_plan_nodes = e.nnodes;
797  instrument = GetInstrumentationArray(instrumentation);
798  for (i = 0; i < nworkers * e.nnodes; ++i)
799  InstrInit(&instrument[i], estate->es_instrument);
801  instrumentation);
802  pei->instrumentation = instrumentation;
803 
804  if (estate->es_jit_flags != PGJIT_NONE)
805  {
806  jit_instrumentation = shm_toc_allocate(pcxt->toc,
807  jit_instrumentation_len);
808  jit_instrumentation->num_workers = nworkers;
809  memset(jit_instrumentation->jit_instr, 0,
810  sizeof(JitInstrumentation) * nworkers);
812  jit_instrumentation);
813  pei->jit_instrumentation = jit_instrumentation;
814  }
815  }
816 
817  /*
818  * Create a DSA area that can be used by the leader and all workers.
819  * (However, if we failed to create a DSM and are using private memory
820  * instead, then skip this.)
821  */
822  if (pcxt->seg != NULL)
823  {
824  char *area_space;
825 
826  area_space = shm_toc_allocate(pcxt->toc, dsa_minsize);
827  shm_toc_insert(pcxt->toc, PARALLEL_KEY_DSA, area_space);
828  pei->area = dsa_create_in_place(area_space, dsa_minsize,
830  pcxt->seg);
831 
832  /*
833  * Serialize parameters, if any, using DSA storage. We don't dare use
834  * the main parallel query DSM for this because we might relaunch
835  * workers after the values have changed (and thus the amount of
836  * storage required has changed).
837  */
838  if (!bms_is_empty(sendParams))
839  {
840  pei->param_exec = SerializeParamExecParams(estate, sendParams,
841  pei->area);
842  fpes->param_exec = pei->param_exec;
843  }
844  }
845 
846  /*
847  * Give parallel-aware nodes a chance to initialize their shared data.
848  * This also initializes the elements of instrumentation->ps_instrument,
849  * if it exists.
850  */
851  d.pcxt = pcxt;
852  d.instrumentation = instrumentation;
853  d.nnodes = 0;
854 
855  /* Install our DSA area while initializing the plan. */
856  estate->es_query_dsa = pei->area;
857  ExecParallelInitializeDSM(planstate, &d);
858  estate->es_query_dsa = NULL;
859 
860  /*
861  * Make sure that the world hasn't shifted under our feet. This could
862  * probably just be an Assert(), but let's be conservative for now.
863  */
864  if (e.nnodes != d.nnodes)
865  elog(ERROR, "inconsistent count of PlanState nodes");
866 
867  /* OK, we're ready to rock and roll. */
868  return pei;
869 }
void InitializeParallelDSM(ParallelContext *pcxt)
Definition: parallel.c:205
ParallelContext * CreateParallelContext(const char *library_name, const char *function_name, int nworkers)
Definition: parallel.c:167
#define bms_is_empty(a)
Definition: bitmapset.h:118
#define MAXALIGN(LEN)
Definition: c.h:811
#define Assert(condition)
Definition: c.h:858
size_t Size
Definition: c.h:605
size_t dsa_minimum_size(void)
Definition: dsa.c:1196
#define dsa_create_in_place(place, size, tranch_id, segment)
Definition: dsa.h:122
#define InvalidDsaPointer
Definition: dsa.h:78
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
#define PARALLEL_KEY_BUFFER_USAGE
Definition: execParallel.c:60
#define PARALLEL_KEY_JIT_INSTRUMENTATION
Definition: execParallel.c:65
#define PARALLEL_KEY_PARAMLISTINFO
Definition: execParallel.c:59
#define PARALLEL_TUPLE_QUEUE_SIZE
Definition: execParallel.c:68
static dsa_pointer SerializeParamExecParams(EState *estate, Bitmapset *params, dsa_area *area)
Definition: execParallel.c:354
#define PARALLEL_KEY_INSTRUMENTATION
Definition: execParallel.c:62
static shm_mq_handle ** ExecParallelSetupTupleQueues(ParallelContext *pcxt, bool reinitialize)
Definition: execParallel.c:535
#define PARALLEL_KEY_PLANNEDSTMT
Definition: execParallel.c:58
static bool ExecParallelEstimate(PlanState *planstate, ExecParallelEstimateContext *e)
Definition: execParallel.c:229
#define GetInstrumentationArray(sei)
Definition: execParallel.c:106
#define PARALLEL_KEY_DSA
Definition: execParallel.c:63
#define PARALLEL_KEY_EXECUTOR_FIXED
Definition: execParallel.c:57
static char * ExecSerializePlan(Plan *plan, EState *estate)
Definition: execParallel.c:145
#define PARALLEL_KEY_QUERY_TEXT
Definition: execParallel.c:64
#define PARALLEL_KEY_WAL_USAGE
Definition: execParallel.c:66
static bool ExecParallelInitializeDSM(PlanState *planstate, ExecParallelInitializeDSMContext *d)
Definition: execParallel.c:438
#define GetPerTupleExprContext(estate)
Definition: executor.h:550
void InstrInit(Instrumentation *instr, int instrument_options)
Definition: instrument.c:58
int i
Definition: isn.c:73
struct JitInstrumentation JitInstrumentation
#define PGJIT_NONE
Definition: jit.h:19
@ LWTRANCHE_PARALLEL_QUERY_DSA
Definition: lwlock.h:195
void * palloc0(Size size)
Definition: mcxt.c:1346
void ExecSetParamPlanMulti(const Bitmapset *params, ExprContext *econtext)
Definition: nodeSubplan.c:1268
Size EstimateParamListSpace(ParamListInfo paramLI)
Definition: params.c:167
void SerializeParamList(ParamListInfo paramLI, char **start_address)
Definition: params.c:229
e
Definition: preproc-init.c:82
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
#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 mul_size(Size s1, Size s2)
Definition: shmem.c:510
Snapshot GetActiveSnapshot(void)
Definition: snapmgr.c:770
struct dsa_area * es_query_dsa
Definition: execnodes.h:704
int es_top_eflags
Definition: execnodes.h:676
int es_instrument
Definition: execnodes.h:677
ParamListInfo es_param_list_info
Definition: execnodes.h:661
int es_jit_flags
Definition: execnodes.h:715
const char * es_sourceText
Definition: execnodes.h:634
Snapshot es_snapshot
Definition: execnodes.h:624
SharedExecutorInstrumentation * instrumentation
Definition: execParallel.c:121
dsm_segment * seg
Definition: parallel.h:42
shm_toc_estimator estimator
Definition: parallel.h:41
shm_toc * toc
Definition: parallel.h:44
PlanState * planstate
Definition: execParallel.h:26
struct SharedJitInstrumentation * jit_instrumentation
Definition: execParallel.h:31
BufferUsage * buffer_usage
Definition: execParallel.h:28
dsa_pointer param_exec
Definition: execParallel.h:33
ParallelContext * pcxt
Definition: execParallel.h:27
WalUsage * wal_usage
Definition: execParallel.h:29
shm_mq_handle ** tqueue
Definition: execParallel.h:36
SharedExecutorInstrumentation * instrumentation
Definition: execParallel.h:30
struct TupleQueueReader ** reader
Definition: execParallel.h:37
Plan * plan
Definition: execnodes.h:1118
JitInstrumentation jit_instr[FLEXIBLE_ARRAY_MEMBER]
Definition: jit.h:54

References ParallelExecutorInfo::area, Assert, bms_is_empty, ParallelExecutorInfo::buffer_usage, CreateParallelContext(), dsa_create_in_place, dsa_minimum_size(), FixedParallelExecutorState::eflags, elog, ERROR, EState::es_instrument, EState::es_jit_flags, EState::es_param_list_info, EState::es_query_dsa, EState::es_snapshot, EState::es_sourceText, EState::es_top_eflags, EstimateParamListSpace(), ParallelContext::estimator, ExecParallelEstimate(), ExecParallelInitializeDSM(), ExecParallelSetupTupleQueues(), ExecSerializePlan(), ExecSetParamPlanMulti(), ParallelExecutorInfo::finished, GetActiveSnapshot(), GetInstrumentationArray, GetPerTupleExprContext, i, InitializeParallelDSM(), InstrInit(), SharedExecutorInstrumentation::instrument_offset, SharedExecutorInstrumentation::instrument_options, ExecParallelInitializeDSMContext::instrumentation, ParallelExecutorInfo::instrumentation, InvalidDsaPointer, FixedParallelExecutorState::jit_flags, SharedJitInstrumentation::jit_instr, ParallelExecutorInfo::jit_instrumentation, LWTRANCHE_PARALLEL_QUERY_DSA, MAXALIGN, mul_size(), ExecParallelInitializeDSMContext::nnodes, SharedExecutorInstrumentation::num_plan_nodes, SharedExecutorInstrumentation::num_workers, SharedJitInstrumentation::num_workers, ParallelContext::nworkers, palloc0(), PARALLEL_KEY_BUFFER_USAGE, PARALLEL_KEY_DSA, PARALLEL_KEY_EXECUTOR_FIXED, PARALLEL_KEY_INSTRUMENTATION, PARALLEL_KEY_JIT_INSTRUMENTATION, PARALLEL_KEY_PARAMLISTINFO, PARALLEL_KEY_PLANNEDSTMT, PARALLEL_KEY_QUERY_TEXT, PARALLEL_KEY_WAL_USAGE, PARALLEL_TUPLE_QUEUE_SIZE, FixedParallelExecutorState::param_exec, ParallelExecutorInfo::param_exec, ExecParallelInitializeDSMContext::pcxt, ParallelExecutorInfo::pcxt, PGJIT_NONE, PlanState::plan, ParallelExecutorInfo::planstate, ParallelExecutorInfo::reader, ParallelContext::seg, SerializeParamExecParams(), SerializeParamList(), shm_toc_allocate(), shm_toc_estimate_chunk, shm_toc_estimate_keys, shm_toc_insert(), ParallelContext::toc, ParallelExecutorInfo::tqueue, FixedParallelExecutorState::tuples_needed, and ParallelExecutorInfo::wal_usage.

Referenced by ExecGather(), and ExecGatherMerge().

◆ ExecParallelCleanup()

void ExecParallelCleanup ( ParallelExecutorInfo pei)

Definition at line 1184 of file execParallel.c.

1185 {
1186  /* Accumulate instrumentation, if any. */
1187  if (pei->instrumentation)
1189  pei->instrumentation);
1190 
1191  /* Accumulate JIT instrumentation, if any. */
1192  if (pei->jit_instrumentation)
1194  pei->jit_instrumentation);
1195 
1196  /* Free any serialized parameters. */
1197  if (DsaPointerIsValid(pei->param_exec))
1198  {
1199  dsa_free(pei->area, pei->param_exec);
1201  }
1202  if (pei->area != NULL)
1203  {
1204  dsa_detach(pei->area);
1205  pei->area = NULL;
1206  }
1207  if (pei->pcxt != NULL)
1208  {
1210  pei->pcxt = NULL;
1211  }
1212  pfree(pei);
1213 }
void DestroyParallelContext(ParallelContext *pcxt)
Definition: parallel.c:929
void dsa_detach(dsa_area *area)
Definition: dsa.c:1952
void dsa_free(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:826
#define DsaPointerIsValid(x)
Definition: dsa.h:106
static bool ExecParallelRetrieveInstrumentation(PlanState *planstate, SharedExecutorInstrumentation *instrumentation)
static void ExecParallelRetrieveJitInstrumentation(PlanState *planstate, SharedJitInstrumentation *shared_jit)
void pfree(void *pointer)
Definition: mcxt.c:1520

References ParallelExecutorInfo::area, DestroyParallelContext(), dsa_detach(), dsa_free(), DsaPointerIsValid, ExecParallelRetrieveInstrumentation(), ExecParallelRetrieveJitInstrumentation(), ParallelExecutorInfo::instrumentation, InvalidDsaPointer, ParallelExecutorInfo::jit_instrumentation, ParallelExecutorInfo::param_exec, ParallelExecutorInfo::pcxt, pfree(), and ParallelExecutorInfo::planstate.

Referenced by ExecShutdownGather(), and ExecShutdownGatherMerge().

◆ ExecParallelCreateReaders()

void ExecParallelCreateReaders ( ParallelExecutorInfo pei)

Definition at line 878 of file execParallel.c.

879 {
880  int nworkers = pei->pcxt->nworkers_launched;
881  int i;
882 
883  Assert(pei->reader == NULL);
884 
885  if (nworkers > 0)
886  {
887  pei->reader = (TupleQueueReader **)
888  palloc(nworkers * sizeof(TupleQueueReader *));
889 
890  for (i = 0; i < nworkers; i++)
891  {
892  shm_mq_set_handle(pei->tqueue[i],
893  pei->pcxt->worker[i].bgwhandle);
894  pei->reader[i] = CreateTupleQueueReader(pei->tqueue[i]);
895  }
896  }
897 }
void * palloc(Size size)
Definition: mcxt.c:1316
void shm_mq_set_handle(shm_mq_handle *mqh, BackgroundWorkerHandle *handle)
Definition: shm_mq.c:319
ParallelWorkerInfo * worker
Definition: parallel.h:45
int nworkers_launched
Definition: parallel.h:37
BackgroundWorkerHandle * bgwhandle
Definition: parallel.h:27
TupleQueueReader * CreateTupleQueueReader(shm_mq_handle *handle)
Definition: tqueue.c:139

References Assert, ParallelWorkerInfo::bgwhandle, CreateTupleQueueReader(), i, ParallelContext::nworkers_launched, palloc(), ParallelExecutorInfo::pcxt, ParallelExecutorInfo::reader, shm_mq_set_handle(), ParallelExecutorInfo::tqueue, and ParallelContext::worker.

Referenced by ExecGather(), and ExecGatherMerge().

◆ ExecParallelFinish()

void ExecParallelFinish ( ParallelExecutorInfo pei)

Definition at line 1131 of file execParallel.c.

1132 {
1133  int nworkers = pei->pcxt->nworkers_launched;
1134  int i;
1135 
1136  /* Make this be a no-op if called twice in a row. */
1137  if (pei->finished)
1138  return;
1139 
1140  /*
1141  * Detach from tuple queues ASAP, so that any still-active workers will
1142  * notice that no further results are wanted.
1143  */
1144  if (pei->tqueue != NULL)
1145  {
1146  for (i = 0; i < nworkers; i++)
1147  shm_mq_detach(pei->tqueue[i]);
1148  pfree(pei->tqueue);
1149  pei->tqueue = NULL;
1150  }
1151 
1152  /*
1153  * While we're waiting for the workers to finish, let's get rid of the
1154  * tuple queue readers. (Any other local cleanup could be done here too.)
1155  */
1156  if (pei->reader != NULL)
1157  {
1158  for (i = 0; i < nworkers; i++)
1160  pfree(pei->reader);
1161  pei->reader = NULL;
1162  }
1163 
1164  /* Now wait for the workers to finish. */
1166 
1167  /*
1168  * Next, accumulate buffer/WAL usage. (This must wait for the workers to
1169  * finish, or we might get incomplete data.)
1170  */
1171  for (i = 0; i < nworkers; i++)
1173 
1174  pei->finished = true;
1175 }
void WaitForParallelWorkersToFinish(ParallelContext *pcxt)
Definition: parallel.c:775
void InstrAccumParallelQuery(BufferUsage *bufusage, WalUsage *walusage)
Definition: instrument.c:218
void shm_mq_detach(shm_mq_handle *mqh)
Definition: shm_mq.c:843
void DestroyTupleQueueReader(TupleQueueReader *reader)
Definition: tqueue.c:155

References ParallelExecutorInfo::buffer_usage, DestroyTupleQueueReader(), ParallelExecutorInfo::finished, i, InstrAccumParallelQuery(), ParallelContext::nworkers_launched, ParallelExecutorInfo::pcxt, pfree(), ParallelExecutorInfo::reader, shm_mq_detach(), ParallelExecutorInfo::tqueue, WaitForParallelWorkersToFinish(), and ParallelExecutorInfo::wal_usage.

Referenced by ExecShutdownGatherMergeWorkers(), and ExecShutdownGatherWorkers().

◆ ExecParallelReinitialize()

void ExecParallelReinitialize ( PlanState planstate,
ParallelExecutorInfo pei,
Bitmapset sendParams 
)

Definition at line 904 of file execParallel.c.

907 {
908  EState *estate = planstate->state;
910 
911  /* Old workers must already be shut down */
912  Assert(pei->finished);
913 
914  /*
915  * Force any initplan outputs that we're going to pass to workers to be
916  * evaluated, if they weren't already (see comments in
917  * ExecInitParallelPlan).
918  */
919  ExecSetParamPlanMulti(sendParams, GetPerTupleExprContext(estate));
920 
922  pei->tqueue = ExecParallelSetupTupleQueues(pei->pcxt, true);
923  pei->reader = NULL;
924  pei->finished = false;
925 
926  fpes = shm_toc_lookup(pei->pcxt->toc, PARALLEL_KEY_EXECUTOR_FIXED, false);
927 
928  /* Free any serialized parameters from the last round. */
929  if (DsaPointerIsValid(fpes->param_exec))
930  {
931  dsa_free(pei->area, fpes->param_exec);
933  }
934 
935  /* Serialize current parameter values if required. */
936  if (!bms_is_empty(sendParams))
937  {
938  pei->param_exec = SerializeParamExecParams(estate, sendParams,
939  pei->area);
940  fpes->param_exec = pei->param_exec;
941  }
942 
943  /* Traverse plan tree and let each child node reset associated state. */
944  estate->es_query_dsa = pei->area;
945  ExecParallelReInitializeDSM(planstate, pei->pcxt);
946  estate->es_query_dsa = NULL;
947 }
void ReinitializeParallelDSM(ParallelContext *pcxt)
Definition: parallel.c:488
static bool ExecParallelReInitializeDSM(PlanState *planstate, ParallelContext *pcxt)
Definition: execParallel.c:953
void * shm_toc_lookup(shm_toc *toc, uint64 key, bool noError)
Definition: shm_toc.c:232
EState * state
Definition: execnodes.h:1120

References ParallelExecutorInfo::area, Assert, bms_is_empty, dsa_free(), DsaPointerIsValid, EState::es_query_dsa, ExecParallelReInitializeDSM(), ExecParallelSetupTupleQueues(), ExecSetParamPlanMulti(), ParallelExecutorInfo::finished, GetPerTupleExprContext, InvalidDsaPointer, PARALLEL_KEY_EXECUTOR_FIXED, FixedParallelExecutorState::param_exec, ParallelExecutorInfo::param_exec, ParallelExecutorInfo::pcxt, ParallelExecutorInfo::reader, ReinitializeParallelDSM(), SerializeParamExecParams(), shm_toc_lookup(), PlanState::state, ParallelContext::toc, and ParallelExecutorInfo::tqueue.

Referenced by ExecGather(), and ExecGatherMerge().

◆ ParallelQueryMain()

void ParallelQueryMain ( dsm_segment seg,
shm_toc toc 
)

Definition at line 1400 of file execParallel.c.

1401 {
1403  BufferUsage *buffer_usage;
1404  WalUsage *wal_usage;
1405  DestReceiver *receiver;
1406  QueryDesc *queryDesc;
1407  SharedExecutorInstrumentation *instrumentation;
1408  SharedJitInstrumentation *jit_instrumentation;
1409  int instrument_options = 0;
1410  void *area_space;
1411  dsa_area *area;
1412  ParallelWorkerContext pwcxt;
1413 
1414  /* Get fixed-size state. */
1415  fpes = shm_toc_lookup(toc, PARALLEL_KEY_EXECUTOR_FIXED, false);
1416 
1417  /* Set up DestReceiver, SharedExecutorInstrumentation, and QueryDesc. */
1418  receiver = ExecParallelGetReceiver(seg, toc);
1419  instrumentation = shm_toc_lookup(toc, PARALLEL_KEY_INSTRUMENTATION, true);
1420  if (instrumentation != NULL)
1421  instrument_options = instrumentation->instrument_options;
1422  jit_instrumentation = shm_toc_lookup(toc, PARALLEL_KEY_JIT_INSTRUMENTATION,
1423  true);
1424  queryDesc = ExecParallelGetQueryDesc(toc, receiver, instrument_options);
1425 
1426  /* Setting debug_query_string for individual workers */
1427  debug_query_string = queryDesc->sourceText;
1428 
1429  /* Report workers' query for monitoring purposes */
1431 
1432  /* Attach to the dynamic shared memory area. */
1433  area_space = shm_toc_lookup(toc, PARALLEL_KEY_DSA, false);
1434  area = dsa_attach_in_place(area_space, seg);
1435 
1436  /* Start up the executor */
1437  queryDesc->plannedstmt->jitFlags = fpes->jit_flags;
1438  ExecutorStart(queryDesc, fpes->eflags);
1439 
1440  /* Special executor initialization steps for parallel workers */
1441  queryDesc->planstate->state->es_query_dsa = area;
1442  if (DsaPointerIsValid(fpes->param_exec))
1443  {
1444  char *paramexec_space;
1445 
1446  paramexec_space = dsa_get_address(area, fpes->param_exec);
1447  RestoreParamExecParams(paramexec_space, queryDesc->estate);
1448  }
1449  pwcxt.toc = toc;
1450  pwcxt.seg = seg;
1451  ExecParallelInitializeWorker(queryDesc->planstate, &pwcxt);
1452 
1453  /* Pass down any tuple bound */
1454  ExecSetTupleBound(fpes->tuples_needed, queryDesc->planstate);
1455 
1456  /*
1457  * Prepare to track buffer/WAL usage during query execution.
1458  *
1459  * We do this after starting up the executor to match what happens in the
1460  * leader, which also doesn't count buffer accesses and WAL activity that
1461  * occur during executor startup.
1462  */
1464 
1465  /*
1466  * Run the plan. If we specified a tuple bound, be careful not to demand
1467  * more tuples than that.
1468  */
1469  ExecutorRun(queryDesc,
1471  fpes->tuples_needed < 0 ? (int64) 0 : fpes->tuples_needed,
1472  true);
1473 
1474  /* Shut down the executor */
1475  ExecutorFinish(queryDesc);
1476 
1477  /* Report buffer/WAL usage during parallel execution. */
1478  buffer_usage = shm_toc_lookup(toc, PARALLEL_KEY_BUFFER_USAGE, false);
1479  wal_usage = shm_toc_lookup(toc, PARALLEL_KEY_WAL_USAGE, false);
1481  &wal_usage[ParallelWorkerNumber]);
1482 
1483  /* Report instrumentation data if any instrumentation options are set. */
1484  if (instrumentation != NULL)
1486  instrumentation);
1487 
1488  /* Report JIT instrumentation data if any */
1489  if (queryDesc->estate->es_jit && jit_instrumentation != NULL)
1490  {
1491  Assert(ParallelWorkerNumber < jit_instrumentation->num_workers);
1492  jit_instrumentation->jit_instr[ParallelWorkerNumber] =
1493  queryDesc->estate->es_jit->instr;
1494  }
1495 
1496  /* Must do this after capturing instrumentation. */
1497  ExecutorEnd(queryDesc);
1498 
1499  /* Cleanup. */
1500  dsa_detach(area);
1501  FreeQueryDesc(queryDesc);
1502  receiver->rDestroy(receiver);
1503 }
int ParallelWorkerNumber
Definition: parallel.c:112
void pgstat_report_activity(BackendState state, const char *cmd_str)
@ STATE_RUNNING
void * dsa_get_address(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:942
dsa_area * dsa_attach_in_place(void *place, dsm_segment *segment)
Definition: dsa.c:545
void ExecutorEnd(QueryDesc *queryDesc)
Definition: execMain.c:467
void ExecutorFinish(QueryDesc *queryDesc)
Definition: execMain.c:407
void ExecutorStart(QueryDesc *queryDesc, int eflags)
Definition: execMain.c:124
void ExecutorRun(QueryDesc *queryDesc, ScanDirection direction, uint64 count, bool execute_once)
Definition: execMain.c:297
static DestReceiver * ExecParallelGetReceiver(dsm_segment *seg, shm_toc *toc)
static bool ExecParallelInitializeWorker(PlanState *planstate, ParallelWorkerContext *pwcxt)
static QueryDesc * ExecParallelGetQueryDesc(shm_toc *toc, DestReceiver *receiver, int instrument_options)
static bool ExecParallelReportInstrumentation(PlanState *planstate, SharedExecutorInstrumentation *instrumentation)
static void RestoreParamExecParams(char *start_address, EState *estate)
Definition: execParallel.c:409
void ExecSetTupleBound(int64 tuples_needed, PlanState *child_node)
Definition: execProcnode.c:843
void InstrEndParallelQuery(BufferUsage *bufusage, WalUsage *walusage)
Definition: instrument.c:208
void InstrStartParallelQuery(void)
Definition: instrument.c:200
const char * debug_query_string
Definition: postgres.c:87
void FreeQueryDesc(QueryDesc *qdesc)
Definition: pquery.c:105
@ ForwardScanDirection
Definition: sdir.h:28
struct JitContext * es_jit
Definition: execnodes.h:716
JitInstrumentation instr
Definition: jit.h:64
dsm_segment * seg
Definition: parallel.h:52
int jitFlags
Definition: plannodes.h:68
const char * sourceText
Definition: execdesc.h:38
EState * estate
Definition: execdesc.h:48
PlannedStmt * plannedstmt
Definition: execdesc.h:37
PlanState * planstate
Definition: execdesc.h:49
void(* rDestroy)(DestReceiver *self)
Definition: dest.h:126
Definition: dsa.c:348

References Assert, debug_query_string, dsa_attach_in_place(), dsa_detach(), dsa_get_address(), DsaPointerIsValid, FixedParallelExecutorState::eflags, EState::es_jit, EState::es_query_dsa, QueryDesc::estate, ExecParallelGetQueryDesc(), ExecParallelGetReceiver(), ExecParallelInitializeWorker(), ExecParallelReportInstrumentation(), ExecSetTupleBound(), ExecutorEnd(), ExecutorFinish(), ExecutorRun(), ExecutorStart(), ForwardScanDirection, FreeQueryDesc(), JitContext::instr, InstrEndParallelQuery(), InstrStartParallelQuery(), SharedExecutorInstrumentation::instrument_options, FixedParallelExecutorState::jit_flags, SharedJitInstrumentation::jit_instr, PlannedStmt::jitFlags, PARALLEL_KEY_BUFFER_USAGE, PARALLEL_KEY_DSA, PARALLEL_KEY_EXECUTOR_FIXED, PARALLEL_KEY_INSTRUMENTATION, PARALLEL_KEY_JIT_INSTRUMENTATION, PARALLEL_KEY_WAL_USAGE, ParallelWorkerNumber, FixedParallelExecutorState::param_exec, pgstat_report_activity(), QueryDesc::plannedstmt, QueryDesc::planstate, _DestReceiver::rDestroy, RestoreParamExecParams(), ParallelWorkerContext::seg, shm_toc_lookup(), QueryDesc::sourceText, PlanState::state, STATE_RUNNING, ParallelWorkerContext::toc, and FixedParallelExecutorState::tuples_needed.