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 589 of file execParallel.c.

592 {
594  ParallelContext *pcxt;
598  char *pstmt_data;
599  char *pstmt_space;
600  char *paramlistinfo_space;
601  BufferUsage *bufusage_space;
602  WalUsage *walusage_space;
603  SharedExecutorInstrumentation *instrumentation = NULL;
604  SharedJitInstrumentation *jit_instrumentation = NULL;
605  int pstmt_len;
606  int paramlistinfo_len;
607  int instrumentation_len = 0;
608  int jit_instrumentation_len = 0;
609  int instrument_offset = 0;
610  Size dsa_minsize = dsa_minimum_size();
611  char *query_string;
612  int query_len;
613 
614  /*
615  * Force any initplan outputs that we're going to pass to workers to be
616  * evaluated, if they weren't already.
617  *
618  * For simplicity, we use the EState's per-output-tuple ExprContext here.
619  * That risks intra-query memory leakage, since we might pass through here
620  * many times before that ExprContext gets reset; but ExecSetParamPlan
621  * doesn't normally leak any memory in the context (see its comments), so
622  * it doesn't seem worth complicating this function's API to pass it a
623  * shorter-lived ExprContext. This might need to change someday.
624  */
625  ExecSetParamPlanMulti(sendParams, GetPerTupleExprContext(estate));
626 
627  /* Allocate object for return value. */
628  pei = palloc0(sizeof(ParallelExecutorInfo));
629  pei->finished = false;
630  pei->planstate = planstate;
631 
632  /* Fix up and serialize plan to be sent to workers. */
633  pstmt_data = ExecSerializePlan(planstate->plan, estate);
634 
635  /* Create a parallel context. */
636  pcxt = CreateParallelContext("postgres", "ParallelQueryMain", nworkers);
637  pei->pcxt = pcxt;
638 
639  /*
640  * Before telling the parallel context to create a dynamic shared memory
641  * segment, we need to figure out how big it should be. Estimate space
642  * for the various things we need to store.
643  */
644 
645  /* Estimate space for fixed-size state. */
648  shm_toc_estimate_keys(&pcxt->estimator, 1);
649 
650  /* Estimate space for query text. */
651  query_len = strlen(estate->es_sourceText);
652  shm_toc_estimate_chunk(&pcxt->estimator, query_len + 1);
653  shm_toc_estimate_keys(&pcxt->estimator, 1);
654 
655  /* Estimate space for serialized PlannedStmt. */
656  pstmt_len = strlen(pstmt_data) + 1;
657  shm_toc_estimate_chunk(&pcxt->estimator, pstmt_len);
658  shm_toc_estimate_keys(&pcxt->estimator, 1);
659 
660  /* Estimate space for serialized ParamListInfo. */
661  paramlistinfo_len = EstimateParamListSpace(estate->es_param_list_info);
662  shm_toc_estimate_chunk(&pcxt->estimator, paramlistinfo_len);
663  shm_toc_estimate_keys(&pcxt->estimator, 1);
664 
665  /*
666  * Estimate space for BufferUsage.
667  *
668  * If EXPLAIN is not in use and there are no extensions loaded that care,
669  * we could skip this. But we have no way of knowing whether anyone's
670  * looking at pgBufferUsage, so do it unconditionally.
671  */
673  mul_size(sizeof(BufferUsage), pcxt->nworkers));
674  shm_toc_estimate_keys(&pcxt->estimator, 1);
675 
676  /*
677  * Same thing for WalUsage.
678  */
680  mul_size(sizeof(WalUsage), pcxt->nworkers));
681  shm_toc_estimate_keys(&pcxt->estimator, 1);
682 
683  /* Estimate space for tuple queues. */
686  shm_toc_estimate_keys(&pcxt->estimator, 1);
687 
688  /*
689  * Give parallel-aware nodes a chance to add to the estimates, and get a
690  * count of how many PlanState nodes there are.
691  */
692  e.pcxt = pcxt;
693  e.nnodes = 0;
694  ExecParallelEstimate(planstate, &e);
695 
696  /* Estimate space for instrumentation, if required. */
697  if (estate->es_instrument)
698  {
699  instrumentation_len =
700  offsetof(SharedExecutorInstrumentation, plan_node_id) +
701  sizeof(int) * e.nnodes;
702  instrumentation_len = MAXALIGN(instrumentation_len);
703  instrument_offset = instrumentation_len;
704  instrumentation_len +=
705  mul_size(sizeof(Instrumentation),
706  mul_size(e.nnodes, nworkers));
707  shm_toc_estimate_chunk(&pcxt->estimator, instrumentation_len);
708  shm_toc_estimate_keys(&pcxt->estimator, 1);
709 
710  /* Estimate space for JIT instrumentation, if required. */
711  if (estate->es_jit_flags != PGJIT_NONE)
712  {
713  jit_instrumentation_len =
714  offsetof(SharedJitInstrumentation, jit_instr) +
715  sizeof(JitInstrumentation) * nworkers;
716  shm_toc_estimate_chunk(&pcxt->estimator, jit_instrumentation_len);
717  shm_toc_estimate_keys(&pcxt->estimator, 1);
718  }
719  }
720 
721  /* Estimate space for DSA area. */
722  shm_toc_estimate_chunk(&pcxt->estimator, dsa_minsize);
723  shm_toc_estimate_keys(&pcxt->estimator, 1);
724 
725  /* Everyone's had a chance to ask for space, so now create the DSM. */
726  InitializeParallelDSM(pcxt);
727 
728  /*
729  * OK, now we have a dynamic shared memory segment, and it should be big
730  * enough to store all of the data we estimated we would want to put into
731  * it, plus whatever general stuff (not specifically executor-related) the
732  * ParallelContext itself needs to store there. None of the space we
733  * asked for has been allocated or initialized yet, though, so do that.
734  */
735 
736  /* Store fixed-size state. */
737  fpes = shm_toc_allocate(pcxt->toc, sizeof(FixedParallelExecutorState));
738  fpes->tuples_needed = tuples_needed;
740  fpes->eflags = estate->es_top_eflags;
741  fpes->jit_flags = estate->es_jit_flags;
743 
744  /* Store query string */
745  query_string = shm_toc_allocate(pcxt->toc, query_len + 1);
746  memcpy(query_string, estate->es_sourceText, query_len + 1);
747  shm_toc_insert(pcxt->toc, PARALLEL_KEY_QUERY_TEXT, query_string);
748 
749  /* Store serialized PlannedStmt. */
750  pstmt_space = shm_toc_allocate(pcxt->toc, pstmt_len);
751  memcpy(pstmt_space, pstmt_data, pstmt_len);
752  shm_toc_insert(pcxt->toc, PARALLEL_KEY_PLANNEDSTMT, pstmt_space);
753 
754  /* Store serialized ParamListInfo. */
755  paramlistinfo_space = shm_toc_allocate(pcxt->toc, paramlistinfo_len);
756  shm_toc_insert(pcxt->toc, PARALLEL_KEY_PARAMLISTINFO, paramlistinfo_space);
757  SerializeParamList(estate->es_param_list_info, &paramlistinfo_space);
758 
759  /* Allocate space for each worker's BufferUsage; no need to initialize. */
760  bufusage_space = shm_toc_allocate(pcxt->toc,
761  mul_size(sizeof(BufferUsage), pcxt->nworkers));
762  shm_toc_insert(pcxt->toc, PARALLEL_KEY_BUFFER_USAGE, bufusage_space);
763  pei->buffer_usage = bufusage_space;
764 
765  /* Same for WalUsage. */
766  walusage_space = shm_toc_allocate(pcxt->toc,
767  mul_size(sizeof(WalUsage), pcxt->nworkers));
768  shm_toc_insert(pcxt->toc, PARALLEL_KEY_WAL_USAGE, walusage_space);
769  pei->wal_usage = walusage_space;
770 
771  /* Set up the tuple queues that the workers will write into. */
772  pei->tqueue = ExecParallelSetupTupleQueues(pcxt, false);
773 
774  /* We don't need the TupleQueueReaders yet, though. */
775  pei->reader = NULL;
776 
777  /*
778  * If instrumentation options were supplied, allocate space for the data.
779  * It only gets partially initialized here; the rest happens during
780  * ExecParallelInitializeDSM.
781  */
782  if (estate->es_instrument)
783  {
784  Instrumentation *instrument;
785  int i;
786 
787  instrumentation = shm_toc_allocate(pcxt->toc, instrumentation_len);
788  instrumentation->instrument_options = estate->es_instrument;
789  instrumentation->instrument_offset = instrument_offset;
790  instrumentation->num_workers = nworkers;
791  instrumentation->num_plan_nodes = e.nnodes;
792  instrument = GetInstrumentationArray(instrumentation);
793  for (i = 0; i < nworkers * e.nnodes; ++i)
794  InstrInit(&instrument[i], estate->es_instrument);
796  instrumentation);
797  pei->instrumentation = instrumentation;
798 
799  if (estate->es_jit_flags != PGJIT_NONE)
800  {
801  jit_instrumentation = shm_toc_allocate(pcxt->toc,
802  jit_instrumentation_len);
803  jit_instrumentation->num_workers = nworkers;
804  memset(jit_instrumentation->jit_instr, 0,
805  sizeof(JitInstrumentation) * nworkers);
807  jit_instrumentation);
808  pei->jit_instrumentation = jit_instrumentation;
809  }
810  }
811 
812  /*
813  * Create a DSA area that can be used by the leader and all workers.
814  * (However, if we failed to create a DSM and are using private memory
815  * instead, then skip this.)
816  */
817  if (pcxt->seg != NULL)
818  {
819  char *area_space;
820 
821  area_space = shm_toc_allocate(pcxt->toc, dsa_minsize);
822  shm_toc_insert(pcxt->toc, PARALLEL_KEY_DSA, area_space);
823  pei->area = dsa_create_in_place(area_space, dsa_minsize,
825  pcxt->seg);
826 
827  /*
828  * Serialize parameters, if any, using DSA storage. We don't dare use
829  * the main parallel query DSM for this because we might relaunch
830  * workers after the values have changed (and thus the amount of
831  * storage required has changed).
832  */
833  if (!bms_is_empty(sendParams))
834  {
835  pei->param_exec = SerializeParamExecParams(estate, sendParams,
836  pei->area);
837  fpes->param_exec = pei->param_exec;
838  }
839  }
840 
841  /*
842  * Give parallel-aware nodes a chance to initialize their shared data.
843  * This also initializes the elements of instrumentation->ps_instrument,
844  * if it exists.
845  */
846  d.pcxt = pcxt;
847  d.instrumentation = instrumentation;
848  d.nnodes = 0;
849 
850  /* Install our DSA area while initializing the plan. */
851  estate->es_query_dsa = pei->area;
852  ExecParallelInitializeDSM(planstate, &d);
853  estate->es_query_dsa = NULL;
854 
855  /*
856  * Make sure that the world hasn't shifted under our feet. This could
857  * probably just be an Assert(), but let's be conservative for now.
858  */
859  if (e.nnodes != d.nnodes)
860  elog(ERROR, "inconsistent count of PlanState nodes");
861 
862  /* OK, we're ready to rock and roll. */
863  return pei;
864 }
void InitializeParallelDSM(ParallelContext *pcxt)
Definition: parallel.c:204
ParallelContext * CreateParallelContext(const char *library_name, const char *function_name, int nworkers)
Definition: parallel.c:166
#define bms_is_empty(a)
Definition: bitmapset.h:105
#define MAXALIGN(LEN)
Definition: c.h:800
size_t Size
Definition: c.h:594
dsa_area * dsa_create_in_place(void *place, size_t size, int tranche_id, dsm_segment *segment)
Definition: dsa.c:482
size_t dsa_minimum_size(void)
Definition: dsa.c:1186
#define InvalidDsaPointer
Definition: dsa.h:78
#define ERROR
Definition: elog.h:39
#define PARALLEL_KEY_BUFFER_USAGE
Definition: execParallel.c:62
#define PARALLEL_KEY_JIT_INSTRUMENTATION
Definition: execParallel.c:67
#define PARALLEL_KEY_PARAMLISTINFO
Definition: execParallel.c:61
#define PARALLEL_TUPLE_QUEUE_SIZE
Definition: execParallel.c:70
static dsa_pointer SerializeParamExecParams(EState *estate, Bitmapset *params, dsa_area *area)
Definition: execParallel.c:356
#define PARALLEL_KEY_INSTRUMENTATION
Definition: execParallel.c:64
static shm_mq_handle ** ExecParallelSetupTupleQueues(ParallelContext *pcxt, bool reinitialize)
Definition: execParallel.c:537
#define PARALLEL_KEY_PLANNEDSTMT
Definition: execParallel.c:60
static bool ExecParallelEstimate(PlanState *planstate, ExecParallelEstimateContext *e)
Definition: execParallel.c:231
#define GetInstrumentationArray(sei)
Definition: execParallel.c:108
#define PARALLEL_KEY_DSA
Definition: execParallel.c:65
#define PARALLEL_KEY_EXECUTOR_FIXED
Definition: execParallel.c:59
static char * ExecSerializePlan(Plan *plan, EState *estate)
Definition: execParallel.c:147
#define PARALLEL_KEY_QUERY_TEXT
Definition: execParallel.c:66
#define PARALLEL_KEY_WAL_USAGE
Definition: execParallel.c:68
static bool ExecParallelInitializeDSM(PlanState *planstate, ExecParallelInitializeDSMContext *d)
Definition: execParallel.c:440
#define GetPerTupleExprContext(estate)
Definition: executor.h:549
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:197
void * palloc0(Size size)
Definition: mcxt.c:1257
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:519
struct dsa_area * es_query_dsa
Definition: execnodes.h:696
int es_top_eflags
Definition: execnodes.h:668
int es_instrument
Definition: execnodes.h:669
ParamListInfo es_param_list_info
Definition: execnodes.h:653
int es_jit_flags
Definition: execnodes.h:707
const char * es_sourceText
Definition: execnodes.h:626
SharedExecutorInstrumentation * instrumentation
Definition: execParallel.c:123
dsm_segment * seg
Definition: parallel.h:43
shm_toc_estimator estimator
Definition: parallel.h:42
shm_toc * toc
Definition: parallel.h:45
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:1037
JitInstrumentation jit_instr[FLEXIBLE_ARRAY_MEMBER]
Definition: jit.h:54

References ParallelExecutorInfo::area, 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_sourceText, EState::es_top_eflags, EstimateParamListSpace(), ParallelContext::estimator, ExecParallelEstimate(), ExecParallelInitializeDSM(), ExecParallelSetupTupleQueues(), ExecSerializePlan(), ExecSetParamPlanMulti(), ParallelExecutorInfo::finished, 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 1179 of file execParallel.c.

1180 {
1181  /* Accumulate instrumentation, if any. */
1182  if (pei->instrumentation)
1184  pei->instrumentation);
1185 
1186  /* Accumulate JIT instrumentation, if any. */
1187  if (pei->jit_instrumentation)
1189  pei->jit_instrumentation);
1190 
1191  /* Free any serialized parameters. */
1192  if (DsaPointerIsValid(pei->param_exec))
1193  {
1194  dsa_free(pei->area, pei->param_exec);
1196  }
1197  if (pei->area != NULL)
1198  {
1199  dsa_detach(pei->area);
1200  pei->area = NULL;
1201  }
1202  if (pei->pcxt != NULL)
1203  {
1205  pei->pcxt = NULL;
1206  }
1207  pfree(pei);
1208 }
void DestroyParallelContext(ParallelContext *pcxt)
Definition: parallel.c:928
void dsa_detach(dsa_area *area)
Definition: dsa.c:1932
void dsa_free(dsa_area *area, dsa_pointer dp)
Definition: dsa.c:833
#define DsaPointerIsValid(x)
Definition: dsa.h:81
static bool ExecParallelRetrieveInstrumentation(PlanState *planstate, SharedExecutorInstrumentation *instrumentation)
static void ExecParallelRetrieveJitInstrumentation(PlanState *planstate, SharedJitInstrumentation *shared_jit)
void pfree(void *pointer)
Definition: mcxt.c:1456

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 873 of file execParallel.c.

874 {
875  int nworkers = pei->pcxt->nworkers_launched;
876  int i;
877 
878  Assert(pei->reader == NULL);
879 
880  if (nworkers > 0)
881  {
882  pei->reader = (TupleQueueReader **)
883  palloc(nworkers * sizeof(TupleQueueReader *));
884 
885  for (i = 0; i < nworkers; i++)
886  {
887  shm_mq_set_handle(pei->tqueue[i],
888  pei->pcxt->worker[i].bgwhandle);
889  pei->reader[i] = CreateTupleQueueReader(pei->tqueue[i]);
890  }
891  }
892 }
Assert(fmt[strlen(fmt) - 1] !='\n')
void * palloc(Size size)
Definition: mcxt.c:1226
void shm_mq_set_handle(shm_mq_handle *mqh, BackgroundWorkerHandle *handle)
Definition: shm_mq.c:320
ParallelWorkerInfo * worker
Definition: parallel.h:46
int nworkers_launched
Definition: parallel.h:38
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 1126 of file execParallel.c.

1127 {
1128  int nworkers = pei->pcxt->nworkers_launched;
1129  int i;
1130 
1131  /* Make this be a no-op if called twice in a row. */
1132  if (pei->finished)
1133  return;
1134 
1135  /*
1136  * Detach from tuple queues ASAP, so that any still-active workers will
1137  * notice that no further results are wanted.
1138  */
1139  if (pei->tqueue != NULL)
1140  {
1141  for (i = 0; i < nworkers; i++)
1142  shm_mq_detach(pei->tqueue[i]);
1143  pfree(pei->tqueue);
1144  pei->tqueue = NULL;
1145  }
1146 
1147  /*
1148  * While we're waiting for the workers to finish, let's get rid of the
1149  * tuple queue readers. (Any other local cleanup could be done here too.)
1150  */
1151  if (pei->reader != NULL)
1152  {
1153  for (i = 0; i < nworkers; i++)
1155  pfree(pei->reader);
1156  pei->reader = NULL;
1157  }
1158 
1159  /* Now wait for the workers to finish. */
1161 
1162  /*
1163  * Next, accumulate buffer/WAL usage. (This must wait for the workers to
1164  * finish, or we might get incomplete data.)
1165  */
1166  for (i = 0; i < nworkers; i++)
1168 
1169  pei->finished = true;
1170 }
void WaitForParallelWorkersToFinish(ParallelContext *pcxt)
Definition: parallel.c:774
void InstrAccumParallelQuery(BufferUsage *bufusage, WalUsage *walusage)
Definition: instrument.c:218
void shm_mq_detach(shm_mq_handle *mqh)
Definition: shm_mq.c:844
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 899 of file execParallel.c.

902 {
903  EState *estate = planstate->state;
905 
906  /* Old workers must already be shut down */
907  Assert(pei->finished);
908 
909  /*
910  * Force any initplan outputs that we're going to pass to workers to be
911  * evaluated, if they weren't already (see comments in
912  * ExecInitParallelPlan).
913  */
914  ExecSetParamPlanMulti(sendParams, GetPerTupleExprContext(estate));
915 
917  pei->tqueue = ExecParallelSetupTupleQueues(pei->pcxt, true);
918  pei->reader = NULL;
919  pei->finished = false;
920 
921  fpes = shm_toc_lookup(pei->pcxt->toc, PARALLEL_KEY_EXECUTOR_FIXED, false);
922 
923  /* Free any serialized parameters from the last round. */
924  if (DsaPointerIsValid(fpes->param_exec))
925  {
926  dsa_free(pei->area, fpes->param_exec);
928  }
929 
930  /* Serialize current parameter values if required. */
931  if (!bms_is_empty(sendParams))
932  {
933  pei->param_exec = SerializeParamExecParams(estate, sendParams,
934  pei->area);
935  fpes->param_exec = pei->param_exec;
936  }
937 
938  /* Traverse plan tree and let each child node reset associated state. */
939  estate->es_query_dsa = pei->area;
940  ExecParallelReInitializeDSM(planstate, pei->pcxt);
941  estate->es_query_dsa = NULL;
942 }
void ReinitializeParallelDSM(ParallelContext *pcxt)
Definition: parallel.c:487
static bool ExecParallelReInitializeDSM(PlanState *planstate, ParallelContext *pcxt)
Definition: execParallel.c:948
void * shm_toc_lookup(shm_toc *toc, uint64 key, bool noError)
Definition: shm_toc.c:232
EState * state
Definition: execnodes.h:1039

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 1395 of file execParallel.c.

1396 {
1398  BufferUsage *buffer_usage;
1399  WalUsage *wal_usage;
1400  DestReceiver *receiver;
1401  QueryDesc *queryDesc;
1402  SharedExecutorInstrumentation *instrumentation;
1403  SharedJitInstrumentation *jit_instrumentation;
1404  int instrument_options = 0;
1405  void *area_space;
1406  dsa_area *area;
1407  ParallelWorkerContext pwcxt;
1408 
1409  /* Get fixed-size state. */
1410  fpes = shm_toc_lookup(toc, PARALLEL_KEY_EXECUTOR_FIXED, false);
1411 
1412  /* Set up DestReceiver, SharedExecutorInstrumentation, and QueryDesc. */
1413  receiver = ExecParallelGetReceiver(seg, toc);
1414  instrumentation = shm_toc_lookup(toc, PARALLEL_KEY_INSTRUMENTATION, true);
1415  if (instrumentation != NULL)
1416  instrument_options = instrumentation->instrument_options;
1417  jit_instrumentation = shm_toc_lookup(toc, PARALLEL_KEY_JIT_INSTRUMENTATION,
1418  true);
1419  queryDesc = ExecParallelGetQueryDesc(toc, receiver, instrument_options);
1420 
1421  /* Setting debug_query_string for individual workers */
1422  debug_query_string = queryDesc->sourceText;
1423 
1424  /* Report workers' query for monitoring purposes */
1426 
1427  /* Attach to the dynamic shared memory area. */
1428  area_space = shm_toc_lookup(toc, PARALLEL_KEY_DSA, false);
1429  area = dsa_attach_in_place(area_space, seg);
1430 
1431  /* Start up the executor */
1432  queryDesc->plannedstmt->jitFlags = fpes->jit_flags;
1433  ExecutorStart(queryDesc, fpes->eflags);
1434 
1435  /* Special executor initialization steps for parallel workers */
1436  queryDesc->planstate->state->es_query_dsa = area;
1437  if (DsaPointerIsValid(fpes->param_exec))
1438  {
1439  char *paramexec_space;
1440 
1441  paramexec_space = dsa_get_address(area, fpes->param_exec);
1442  RestoreParamExecParams(paramexec_space, queryDesc->estate);
1443  }
1444  pwcxt.toc = toc;
1445  pwcxt.seg = seg;
1446  ExecParallelInitializeWorker(queryDesc->planstate, &pwcxt);
1447 
1448  /* Pass down any tuple bound */
1449  ExecSetTupleBound(fpes->tuples_needed, queryDesc->planstate);
1450 
1451  /*
1452  * Prepare to track buffer/WAL usage during query execution.
1453  *
1454  * We do this after starting up the executor to match what happens in the
1455  * leader, which also doesn't count buffer accesses and WAL activity that
1456  * occur during executor startup.
1457  */
1459 
1460  /*
1461  * Run the plan. If we specified a tuple bound, be careful not to demand
1462  * more tuples than that.
1463  */
1464  ExecutorRun(queryDesc,
1466  fpes->tuples_needed < 0 ? (int64) 0 : fpes->tuples_needed,
1467  true);
1468 
1469  /* Shut down the executor */
1470  ExecutorFinish(queryDesc);
1471 
1472  /* Report buffer/WAL usage during parallel execution. */
1473  buffer_usage = shm_toc_lookup(toc, PARALLEL_KEY_BUFFER_USAGE, false);
1474  wal_usage = shm_toc_lookup(toc, PARALLEL_KEY_WAL_USAGE, false);
1476  &wal_usage[ParallelWorkerNumber]);
1477 
1478  /* Report instrumentation data if any instrumentation options are set. */
1479  if (instrumentation != NULL)
1481  instrumentation);
1482 
1483  /* Report JIT instrumentation data if any */
1484  if (queryDesc->estate->es_jit && jit_instrumentation != NULL)
1485  {
1486  Assert(ParallelWorkerNumber < jit_instrumentation->num_workers);
1487  jit_instrumentation->jit_instr[ParallelWorkerNumber] =
1488  queryDesc->estate->es_jit->instr;
1489  }
1490 
1491  /* Must do this after capturing instrumentation. */
1492  ExecutorEnd(queryDesc);
1493 
1494  /* Cleanup. */
1495  dsa_detach(area);
1496  FreeQueryDesc(queryDesc);
1497  receiver->rDestroy(receiver);
1498 }
int ParallelWorkerNumber
Definition: parallel.c:114
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:949
dsa_area * dsa_attach_in_place(void *place, dsm_segment *segment)
Definition: dsa.c:554
void ExecutorEnd(QueryDesc *queryDesc)
Definition: execMain.c:469
void ExecutorFinish(QueryDesc *queryDesc)
Definition: execMain.c:409
void ExecutorStart(QueryDesc *queryDesc, int eflags)
Definition: execMain.c:132
void ExecutorRun(QueryDesc *queryDesc, ScanDirection direction, uint64 count, bool execute_once)
Definition: execMain.c:302
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:411
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:85
void FreeQueryDesc(QueryDesc *qdesc)
Definition: pquery.c:105
@ ForwardScanDirection
Definition: sdir.h:28
struct JitContext * es_jit
Definition: execnodes.h:708
JitInstrumentation instr
Definition: jit.h:64
dsm_segment * seg
Definition: parallel.h:53
int jitFlags
Definition: plannodes.h:69
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:125
Definition: dsa.c:367

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.