f0661c4e8c
In addition, this path fills in a number of missing bits and pieces in the parallel infrastructure. Paths and plans now have a parallel_aware flag indicating whether whatever parallel-aware logic they have should be engaged. It is believed that we will need this flag for a number of path/plan types, not just sequential scans, which is why the flag is generic rather than part of the SeqScan structures specifically. Also, execParallel.c now gives parallel nodes a chance to initialize their PlanState nodes from the DSM during parallel worker startup. Amit Kapila, with a fair amount of adjustment by me. Review of previous patch versions by Haribabu Kommi and others.
670 lines
21 KiB
C
670 lines
21 KiB
C
/*-------------------------------------------------------------------------
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*
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* execParallel.c
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* Support routines for parallel execution.
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*
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* Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* This file contains routines that are intended to support setting up,
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* using, and tearing down a ParallelContext from within the PostgreSQL
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* executor. The ParallelContext machinery will handle starting the
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* workers and ensuring that their state generally matches that of the
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* leader; see src/backend/access/transam/README.parallel for details.
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* However, we must save and restore relevant executor state, such as
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* any ParamListInfo associated with the query, buffer usage info, and
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* the actual plan to be passed down to the worker.
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*
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* IDENTIFICATION
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* src/backend/executor/execParallel.c
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*
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*-------------------------------------------------------------------------
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*/
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#include "postgres.h"
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#include "executor/execParallel.h"
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#include "executor/executor.h"
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#include "executor/nodeSeqscan.h"
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#include "executor/tqueue.h"
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#include "nodes/nodeFuncs.h"
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#include "optimizer/planmain.h"
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#include "optimizer/planner.h"
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#include "storage/spin.h"
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#include "tcop/tcopprot.h"
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#include "utils/memutils.h"
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#include "utils/snapmgr.h"
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/*
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* Magic numbers for parallel executor communication. We use constants
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* greater than any 32-bit integer here so that values < 2^32 can be used
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* by individual parallel nodes to store their own state.
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*/
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#define PARALLEL_KEY_PLANNEDSTMT UINT64CONST(0xE000000000000001)
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#define PARALLEL_KEY_PARAMS UINT64CONST(0xE000000000000002)
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#define PARALLEL_KEY_BUFFER_USAGE UINT64CONST(0xE000000000000003)
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#define PARALLEL_KEY_TUPLE_QUEUE UINT64CONST(0xE000000000000004)
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#define PARALLEL_KEY_INSTRUMENTATION UINT64CONST(0xE000000000000005)
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#define PARALLEL_TUPLE_QUEUE_SIZE 65536
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/* DSM structure for accumulating per-PlanState instrumentation. */
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typedef struct SharedPlanStateInstrumentation
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{
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int plan_node_id;
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slock_t mutex;
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Instrumentation instr;
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} SharedPlanStateInstrumentation;
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/* DSM structure for accumulating per-PlanState instrumentation. */
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struct SharedExecutorInstrumentation
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{
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int instrument_options;
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int ps_ninstrument; /* # of ps_instrument structures following */
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SharedPlanStateInstrumentation ps_instrument[FLEXIBLE_ARRAY_MEMBER];
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};
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/* Context object for ExecParallelEstimate. */
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typedef struct ExecParallelEstimateContext
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{
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ParallelContext *pcxt;
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int nnodes;
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} ExecParallelEstimateContext;
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/* Context object for ExecParallelEstimate. */
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typedef struct ExecParallelInitializeDSMContext
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{
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ParallelContext *pcxt;
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SharedExecutorInstrumentation *instrumentation;
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int nnodes;
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} ExecParallelInitializeDSMContext;
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/* Helper functions that run in the parallel leader. */
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static char *ExecSerializePlan(Plan *plan, EState *estate);
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static bool ExecParallelEstimate(PlanState *node,
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ExecParallelEstimateContext *e);
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static bool ExecParallelInitializeDSM(PlanState *node,
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ExecParallelInitializeDSMContext *d);
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static shm_mq_handle **ExecParallelSetupTupleQueues(ParallelContext *pcxt,
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bool reinitialize);
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static bool ExecParallelRetrieveInstrumentation(PlanState *planstate,
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SharedExecutorInstrumentation *instrumentation);
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/* Helper functions that run in the parallel worker. */
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static void ParallelQueryMain(dsm_segment *seg, shm_toc *toc);
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static DestReceiver *ExecParallelGetReceiver(dsm_segment *seg, shm_toc *toc);
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/*
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* Create a serialized representation of the plan to be sent to each worker.
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*/
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static char *
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ExecSerializePlan(Plan *plan, EState *estate)
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{
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PlannedStmt *pstmt;
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ListCell *tlist;
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/* We can't scribble on the original plan, so make a copy. */
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plan = copyObject(plan);
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/*
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* The worker will start its own copy of the executor, and that copy will
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* insert a junk filter if the toplevel node has any resjunk entries. We
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* don't want that to happen, because while resjunk columns shouldn't be
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* sent back to the user, here the tuples are coming back to another
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* backend which may very well need them. So mutate the target list
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* accordingly. This is sort of a hack; there might be better ways to do
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* this...
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*/
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foreach(tlist, plan->targetlist)
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{
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TargetEntry *tle = (TargetEntry *) lfirst(tlist);
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tle->resjunk = false;
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}
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/*
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* Create a dummy PlannedStmt. Most of the fields don't need to be valid
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* for our purposes, but the worker will need at least a minimal
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* PlannedStmt to start the executor.
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*/
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pstmt = makeNode(PlannedStmt);
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pstmt->commandType = CMD_SELECT;
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pstmt->queryId = 0;
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pstmt->hasReturning = 0;
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pstmt->hasModifyingCTE = 0;
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pstmt->canSetTag = 1;
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pstmt->transientPlan = 0;
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pstmt->planTree = plan;
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pstmt->rtable = estate->es_range_table;
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pstmt->resultRelations = NIL;
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pstmt->utilityStmt = NULL;
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pstmt->subplans = NIL;
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pstmt->rewindPlanIDs = NULL;
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pstmt->rowMarks = NIL;
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pstmt->nParamExec = estate->es_plannedstmt->nParamExec;
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pstmt->relationOids = NIL;
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pstmt->invalItems = NIL; /* workers can't replan anyway... */
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pstmt->hasRowSecurity = false;
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/* Return serialized copy of our dummy PlannedStmt. */
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return nodeToString(pstmt);
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}
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/*
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* Ordinary plan nodes won't do anything here, but parallel-aware plan nodes
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* may need some state which is shared across all parallel workers. Before
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* we size the DSM, give them a chance to call shm_toc_estimate_chunk or
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* shm_toc_estimate_keys on &pcxt->estimator.
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*
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* While we're at it, count the number of PlanState nodes in the tree, so
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* we know how many SharedPlanStateInstrumentation structures we need.
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*/
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static bool
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ExecParallelEstimate(PlanState *planstate, ExecParallelEstimateContext *e)
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{
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if (planstate == NULL)
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return false;
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/* Count this node. */
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e->nnodes++;
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/* Call estimators for parallel-aware nodes. */
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switch (nodeTag(planstate))
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{
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case T_SeqScanState:
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ExecSeqScanEstimate((SeqScanState *) planstate,
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e->pcxt);
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break;
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default:
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break;
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}
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return planstate_tree_walker(planstate, ExecParallelEstimate, e);
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}
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/*
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* Ordinary plan nodes won't do anything here, but parallel-aware plan nodes
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* may need to initialize shared state in the DSM before parallel workers
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* are available. They can allocate the space they previous estimated using
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* shm_toc_allocate, and add the keys they previously estimated using
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* shm_toc_insert, in each case targeting pcxt->toc.
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*/
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static bool
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ExecParallelInitializeDSM(PlanState *planstate,
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ExecParallelInitializeDSMContext *d)
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{
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if (planstate == NULL)
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return false;
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/* If instrumentation is enabled, initialize array slot for this node. */
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if (d->instrumentation != NULL)
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{
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SharedPlanStateInstrumentation *instrumentation;
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instrumentation = &d->instrumentation->ps_instrument[d->nnodes];
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Assert(d->nnodes < d->instrumentation->ps_ninstrument);
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instrumentation->plan_node_id = planstate->plan->plan_node_id;
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SpinLockInit(&instrumentation->mutex);
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InstrInit(&instrumentation->instr,
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d->instrumentation->instrument_options);
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}
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/* Count this node. */
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d->nnodes++;
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/* Call initializers for parallel-aware plan nodes. */
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switch (nodeTag(planstate))
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{
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case T_SeqScanState:
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ExecSeqScanInitializeDSM((SeqScanState *) planstate,
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d->pcxt);
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break;
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default:
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break;
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}
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return planstate_tree_walker(planstate, ExecParallelInitializeDSM, d);
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}
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/*
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* It sets up the response queues for backend workers to return tuples
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* to the main backend and start the workers.
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*/
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static shm_mq_handle **
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ExecParallelSetupTupleQueues(ParallelContext *pcxt, bool reinitialize)
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{
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shm_mq_handle **responseq;
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char *tqueuespace;
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int i;
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/* Skip this if no workers. */
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if (pcxt->nworkers == 0)
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return NULL;
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/* Allocate memory for shared memory queue handles. */
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responseq = (shm_mq_handle **)
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palloc(pcxt->nworkers * sizeof(shm_mq_handle *));
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/*
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* If not reinitializing, allocate space from the DSM for the queues;
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* otherwise, find the already allocated space.
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*/
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if (!reinitialize)
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tqueuespace =
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shm_toc_allocate(pcxt->toc,
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PARALLEL_TUPLE_QUEUE_SIZE * pcxt->nworkers);
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else
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tqueuespace = shm_toc_lookup(pcxt->toc, PARALLEL_KEY_TUPLE_QUEUE);
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/* Create the queues, and become the receiver for each. */
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for (i = 0; i < pcxt->nworkers; ++i)
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{
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shm_mq *mq;
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mq = shm_mq_create(tqueuespace + i * PARALLEL_TUPLE_QUEUE_SIZE,
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(Size) PARALLEL_TUPLE_QUEUE_SIZE);
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shm_mq_set_receiver(mq, MyProc);
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responseq[i] = shm_mq_attach(mq, pcxt->seg, NULL);
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}
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/* Add array of queues to shm_toc, so others can find it. */
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if (!reinitialize)
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shm_toc_insert(pcxt->toc, PARALLEL_KEY_TUPLE_QUEUE, tqueuespace);
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/* Return array of handles. */
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return responseq;
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}
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/*
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* Re-initialize the response queues for backend workers to return tuples
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* to the main backend and start the workers.
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*/
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shm_mq_handle **
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ExecParallelReinitializeTupleQueues(ParallelContext *pcxt)
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{
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return ExecParallelSetupTupleQueues(pcxt, true);
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}
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/*
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* Sets up the required infrastructure for backend workers to perform
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* execution and return results to the main backend.
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*/
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ParallelExecutorInfo *
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ExecInitParallelPlan(PlanState *planstate, EState *estate, int nworkers)
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{
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ParallelExecutorInfo *pei;
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ParallelContext *pcxt;
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ExecParallelEstimateContext e;
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ExecParallelInitializeDSMContext d;
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char *pstmt_data;
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char *pstmt_space;
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char *param_space;
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BufferUsage *bufusage_space;
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SharedExecutorInstrumentation *instrumentation = NULL;
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int pstmt_len;
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int param_len;
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int instrumentation_len = 0;
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/* Allocate object for return value. */
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pei = palloc0(sizeof(ParallelExecutorInfo));
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pei->planstate = planstate;
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/* Fix up and serialize plan to be sent to workers. */
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pstmt_data = ExecSerializePlan(planstate->plan, estate);
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/* Create a parallel context. */
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pcxt = CreateParallelContext(ParallelQueryMain, nworkers);
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pei->pcxt = pcxt;
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/*
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* Before telling the parallel context to create a dynamic shared memory
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* segment, we need to figure out how big it should be. Estimate space
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* for the various things we need to store.
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*/
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/* Estimate space for serialized PlannedStmt. */
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pstmt_len = strlen(pstmt_data) + 1;
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shm_toc_estimate_chunk(&pcxt->estimator, pstmt_len);
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shm_toc_estimate_keys(&pcxt->estimator, 1);
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/* Estimate space for serialized ParamListInfo. */
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param_len = EstimateParamListSpace(estate->es_param_list_info);
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shm_toc_estimate_chunk(&pcxt->estimator, param_len);
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shm_toc_estimate_keys(&pcxt->estimator, 1);
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/*
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* Estimate space for BufferUsage.
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*
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* If EXPLAIN is not in use and there are no extensions loaded that care,
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* we could skip this. But we have no way of knowing whether anyone's
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* looking at pgBufferUsage, so do it unconditionally.
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*/
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shm_toc_estimate_chunk(&pcxt->estimator,
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sizeof(BufferUsage) * pcxt->nworkers);
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shm_toc_estimate_keys(&pcxt->estimator, 1);
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/* Estimate space for tuple queues. */
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shm_toc_estimate_chunk(&pcxt->estimator,
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PARALLEL_TUPLE_QUEUE_SIZE * pcxt->nworkers);
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shm_toc_estimate_keys(&pcxt->estimator, 1);
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/*
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* Give parallel-aware nodes a chance to add to the estimates, and get
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* a count of how many PlanState nodes there are.
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*/
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e.pcxt = pcxt;
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e.nnodes = 0;
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ExecParallelEstimate(planstate, &e);
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/* Estimate space for instrumentation, if required. */
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if (estate->es_instrument)
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{
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instrumentation_len =
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offsetof(SharedExecutorInstrumentation, ps_instrument)
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+ sizeof(SharedPlanStateInstrumentation) * e.nnodes;
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shm_toc_estimate_chunk(&pcxt->estimator, instrumentation_len);
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shm_toc_estimate_keys(&pcxt->estimator, 1);
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}
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/* Everyone's had a chance to ask for space, so now create the DSM. */
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InitializeParallelDSM(pcxt);
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/*
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* OK, now we have a dynamic shared memory segment, and it should be big
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* enough to store all of the data we estimated we would want to put into
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* it, plus whatever general stuff (not specifically executor-related) the
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* ParallelContext itself needs to store there. None of the space we
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* asked for has been allocated or initialized yet, though, so do that.
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*/
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/* Store serialized PlannedStmt. */
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pstmt_space = shm_toc_allocate(pcxt->toc, pstmt_len);
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memcpy(pstmt_space, pstmt_data, pstmt_len);
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shm_toc_insert(pcxt->toc, PARALLEL_KEY_PLANNEDSTMT, pstmt_space);
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/* Store serialized ParamListInfo. */
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param_space = shm_toc_allocate(pcxt->toc, param_len);
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shm_toc_insert(pcxt->toc, PARALLEL_KEY_PARAMS, param_space);
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SerializeParamList(estate->es_param_list_info, ¶m_space);
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/* Allocate space for each worker's BufferUsage; no need to initialize. */
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bufusage_space = shm_toc_allocate(pcxt->toc,
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sizeof(BufferUsage) * pcxt->nworkers);
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shm_toc_insert(pcxt->toc, PARALLEL_KEY_BUFFER_USAGE, bufusage_space);
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pei->buffer_usage = bufusage_space;
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/* Set up tuple queues. */
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pei->tqueue = ExecParallelSetupTupleQueues(pcxt, false);
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/*
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* If instrumentation options were supplied, allocate space for the
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* data. It only gets partially initialized here; the rest happens
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* during ExecParallelInitializeDSM.
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*/
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if (estate->es_instrument)
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{
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instrumentation = shm_toc_allocate(pcxt->toc, instrumentation_len);
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instrumentation->instrument_options = estate->es_instrument;
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instrumentation->ps_ninstrument = e.nnodes;
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shm_toc_insert(pcxt->toc, PARALLEL_KEY_INSTRUMENTATION,
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instrumentation);
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pei->instrumentation = instrumentation;
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}
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/*
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* Give parallel-aware nodes a chance to initialize their shared data.
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* This also initializes the elements of instrumentation->ps_instrument,
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* if it exists.
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*/
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d.pcxt = pcxt;
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d.instrumentation = instrumentation;
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d.nnodes = 0;
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ExecParallelInitializeDSM(planstate, &d);
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/*
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* Make sure that the world hasn't shifted under our feat. This could
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* probably just be an Assert(), but let's be conservative for now.
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*/
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if (e.nnodes != d.nnodes)
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elog(ERROR, "inconsistent count of PlanState nodes");
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/* OK, we're ready to rock and roll. */
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return pei;
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}
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/*
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* Copy instrumentation information about this node and its descendents from
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* dynamic shared memory.
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*/
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static bool
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ExecParallelRetrieveInstrumentation(PlanState *planstate,
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SharedExecutorInstrumentation *instrumentation)
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{
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int i;
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int plan_node_id = planstate->plan->plan_node_id;
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SharedPlanStateInstrumentation *ps_instrument;
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/* Find the instumentation for this node. */
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for (i = 0; i < instrumentation->ps_ninstrument; ++i)
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if (instrumentation->ps_instrument[i].plan_node_id == plan_node_id)
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break;
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if (i >= instrumentation->ps_ninstrument)
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elog(ERROR, "plan node %d not found", plan_node_id);
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/* No need to acquire the spinlock here; workers have exited already. */
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ps_instrument = &instrumentation->ps_instrument[i];
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InstrAggNode(planstate->instrument, &ps_instrument->instr);
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return planstate_tree_walker(planstate, ExecParallelRetrieveInstrumentation,
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instrumentation);
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}
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/*
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* Finish parallel execution. We wait for parallel workers to finish, and
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* accumulate their buffer usage and instrumentation.
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*/
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void
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ExecParallelFinish(ParallelExecutorInfo *pei)
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{
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int i;
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/* First, wait for the workers to finish. */
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WaitForParallelWorkersToFinish(pei->pcxt);
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/* Next, accumulate buffer usage. */
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for (i = 0; i < pei->pcxt->nworkers; ++i)
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InstrAccumParallelQuery(&pei->buffer_usage[i]);
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/* Finally, accumulate instrumentation, if any. */
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if (pei->instrumentation)
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ExecParallelRetrieveInstrumentation(pei->planstate,
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pei->instrumentation);
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}
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/*
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* Clean up whatever ParallelExecutreInfo resources still exist after
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* ExecParallelFinish. We separate these routines because someone might
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* want to examine the contents of the DSM after ExecParallelFinish and
|
|
* before calling this routine.
|
|
*/
|
|
void
|
|
ExecParallelCleanup(ParallelExecutorInfo *pei)
|
|
{
|
|
if (pei->pcxt != NULL)
|
|
{
|
|
DestroyParallelContext(pei->pcxt);
|
|
pei->pcxt = NULL;
|
|
}
|
|
pfree(pei);
|
|
}
|
|
|
|
/*
|
|
* Create a DestReceiver to write tuples we produce to the shm_mq designated
|
|
* for that purpose.
|
|
*/
|
|
static DestReceiver *
|
|
ExecParallelGetReceiver(dsm_segment *seg, shm_toc *toc)
|
|
{
|
|
char *mqspace;
|
|
shm_mq *mq;
|
|
|
|
mqspace = shm_toc_lookup(toc, PARALLEL_KEY_TUPLE_QUEUE);
|
|
mqspace += ParallelWorkerNumber * PARALLEL_TUPLE_QUEUE_SIZE;
|
|
mq = (shm_mq *) mqspace;
|
|
shm_mq_set_sender(mq, MyProc);
|
|
return CreateTupleQueueDestReceiver(shm_mq_attach(mq, seg, NULL));
|
|
}
|
|
|
|
/*
|
|
* Create a QueryDesc for the PlannedStmt we are to execute, and return it.
|
|
*/
|
|
static QueryDesc *
|
|
ExecParallelGetQueryDesc(shm_toc *toc, DestReceiver *receiver,
|
|
int instrument_options)
|
|
{
|
|
char *pstmtspace;
|
|
char *paramspace;
|
|
PlannedStmt *pstmt;
|
|
ParamListInfo paramLI;
|
|
|
|
/* Reconstruct leader-supplied PlannedStmt. */
|
|
pstmtspace = shm_toc_lookup(toc, PARALLEL_KEY_PLANNEDSTMT);
|
|
pstmt = (PlannedStmt *) stringToNode(pstmtspace);
|
|
|
|
/* Reconstruct ParamListInfo. */
|
|
paramspace = shm_toc_lookup(toc, PARALLEL_KEY_PARAMS);
|
|
paramLI = RestoreParamList(¶mspace);
|
|
|
|
/*
|
|
* Create a QueryDesc for the query.
|
|
*
|
|
* It's not obvious how to obtain the query string from here; and even if
|
|
* we could copying it would take more cycles than not copying it. But
|
|
* it's a bit unsatisfying to just use a dummy string here, so consider
|
|
* revising this someday.
|
|
*/
|
|
return CreateQueryDesc(pstmt,
|
|
"<parallel query>",
|
|
GetActiveSnapshot(), InvalidSnapshot,
|
|
receiver, paramLI, instrument_options);
|
|
}
|
|
|
|
/*
|
|
* Copy instrumentation information from this node and its descendents into
|
|
* dynamic shared memory, so that the parallel leader can retrieve it.
|
|
*/
|
|
static bool
|
|
ExecParallelReportInstrumentation(PlanState *planstate,
|
|
SharedExecutorInstrumentation *instrumentation)
|
|
{
|
|
int i;
|
|
int plan_node_id = planstate->plan->plan_node_id;
|
|
SharedPlanStateInstrumentation *ps_instrument;
|
|
|
|
/*
|
|
* If we shuffled the plan_node_id values in ps_instrument into sorted
|
|
* order, we could use binary search here. This might matter someday
|
|
* if we're pushing down sufficiently large plan trees. For now, do it
|
|
* the slow, dumb way.
|
|
*/
|
|
for (i = 0; i < instrumentation->ps_ninstrument; ++i)
|
|
if (instrumentation->ps_instrument[i].plan_node_id == plan_node_id)
|
|
break;
|
|
if (i >= instrumentation->ps_ninstrument)
|
|
elog(ERROR, "plan node %d not found", plan_node_id);
|
|
|
|
/*
|
|
* There's one SharedPlanStateInstrumentation per plan_node_id, so we
|
|
* must use a spinlock in case multiple workers report at the same time.
|
|
*/
|
|
ps_instrument = &instrumentation->ps_instrument[i];
|
|
SpinLockAcquire(&ps_instrument->mutex);
|
|
InstrAggNode(&ps_instrument->instr, planstate->instrument);
|
|
SpinLockRelease(&ps_instrument->mutex);
|
|
|
|
return planstate_tree_walker(planstate, ExecParallelReportInstrumentation,
|
|
instrumentation);
|
|
}
|
|
|
|
/*
|
|
* Initialize the PlanState and its descendents with the information
|
|
* retrieved from shared memory. This has to be done once the PlanState
|
|
* is allocated and initialized by executor; that is, after ExecutorStart().
|
|
*/
|
|
static bool
|
|
ExecParallelInitializeWorker(PlanState *planstate, shm_toc *toc)
|
|
{
|
|
if (planstate == NULL)
|
|
return false;
|
|
|
|
/* Call initializers for parallel-aware plan nodes. */
|
|
switch (nodeTag(planstate))
|
|
{
|
|
case T_SeqScanState:
|
|
ExecSeqScanInitializeWorker((SeqScanState *) planstate, toc);
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return planstate_tree_walker(planstate, ExecParallelInitializeWorker, toc);
|
|
}
|
|
|
|
/*
|
|
* Main entrypoint for parallel query worker processes.
|
|
*
|
|
* We reach this function from ParallelMain, so the setup necessary to create
|
|
* a sensible parallel environment has already been done; ParallelMain worries
|
|
* about stuff like the transaction state, combo CID mappings, and GUC values,
|
|
* so we don't need to deal with any of that here.
|
|
*
|
|
* Our job is to deal with concerns specific to the executor. The parallel
|
|
* group leader will have stored a serialized PlannedStmt, and it's our job
|
|
* to execute that plan and write the resulting tuples to the appropriate
|
|
* tuple queue. Various bits of supporting information that we need in order
|
|
* to do this are also stored in the dsm_segment and can be accessed through
|
|
* the shm_toc.
|
|
*/
|
|
static void
|
|
ParallelQueryMain(dsm_segment *seg, shm_toc *toc)
|
|
{
|
|
BufferUsage *buffer_usage;
|
|
DestReceiver *receiver;
|
|
QueryDesc *queryDesc;
|
|
SharedExecutorInstrumentation *instrumentation;
|
|
int instrument_options = 0;
|
|
|
|
/* Set up DestReceiver, SharedExecutorInstrumentation, and QueryDesc. */
|
|
receiver = ExecParallelGetReceiver(seg, toc);
|
|
instrumentation = shm_toc_lookup(toc, PARALLEL_KEY_INSTRUMENTATION);
|
|
if (instrumentation != NULL)
|
|
instrument_options = instrumentation->instrument_options;
|
|
queryDesc = ExecParallelGetQueryDesc(toc, receiver, instrument_options);
|
|
|
|
/* Prepare to track buffer usage during query execution. */
|
|
InstrStartParallelQuery();
|
|
|
|
/* Start up the executor, have it run the plan, and then shut it down. */
|
|
ExecutorStart(queryDesc, 0);
|
|
ExecParallelInitializeWorker(queryDesc->planstate, toc);
|
|
ExecutorRun(queryDesc, ForwardScanDirection, 0L);
|
|
ExecutorFinish(queryDesc);
|
|
|
|
/* Report buffer usage during parallel execution. */
|
|
buffer_usage = shm_toc_lookup(toc, PARALLEL_KEY_BUFFER_USAGE);
|
|
InstrEndParallelQuery(&buffer_usage[ParallelWorkerNumber]);
|
|
|
|
/* Report instrumentation data if any instrumentation options are set. */
|
|
if (instrumentation != NULL)
|
|
ExecParallelReportInstrumentation(queryDesc->planstate,
|
|
instrumentation);
|
|
|
|
/* Must do this after capturing instrumentation. */
|
|
ExecutorEnd(queryDesc);
|
|
|
|
/* Cleanup. */
|
|
FreeQueryDesc(queryDesc);
|
|
(*receiver->rDestroy) (receiver);
|
|
}
|