mirror of https://github.com/postgres/postgres
This code provides infrastructure for a parallel leader to start up parallel workers to execute subtrees of the plan tree being executed in the master. User-supplied parameters from ParamListInfo are passed down, but PARAM_EXEC parameters are not. Various other constructs, such as initplans, subplans, and CTEs, are also not currently shared. Nevertheless, there's enough here to support a basic implementation of parallel query, and we can lift some of the current restrictions as needed. Amit Kapila and Robert Haaspull/7/head
Robert Haas
10 years ago
parent
0557dc276f
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d1b7c1ffe7
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/*-------------------------------------------------------------------------
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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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* |
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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/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, List *rangetable); |
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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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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, List *rangetable) |
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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 = rangetable; |
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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 = 0; |
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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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/*
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* XXX. Call estimators for parallel-aware nodes here, when we have |
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* some. |
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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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/*
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* XXX. Call initializers for parallel-aware plan nodes, when we have |
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* some. |
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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) |
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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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/* Allocate space from the DSM for the queues themselves. */ |
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tqueuespace = shm_toc_allocate(pcxt->toc, |
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PARALLEL_TUPLE_QUEUE_SIZE * pcxt->nworkers); |
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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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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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* 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->es_range_table); |
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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); |
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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; |
||||||
|
int plan_node_id = planstate->plan->plan_node_id; |
||||||
|
SharedPlanStateInstrumentation *ps_instrument; |
||||||
|
|
||||||
|
/* Find the instumentation for this node. */ |
||||||
|
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); |
||||||
|
|
||||||
|
/* No need to acquire the spinlock here; workers have exited already. */ |
||||||
|
ps_instrument = &instrumentation->ps_instrument[i]; |
||||||
|
InstrAggNode(planstate->instrument, &ps_instrument->instr); |
||||||
|
|
||||||
|
return planstate_tree_walker(planstate, ExecParallelRetrieveInstrumentation, |
||||||
|
instrumentation); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* Finish parallel execution. We wait for parallel workers to finish, and |
||||||
|
* accumulate their buffer usage and instrumentation. |
||||||
|
*/ |
||||||
|
void |
||||||
|
ExecParallelFinish(ParallelExecutorInfo *pei) |
||||||
|
{ |
||||||
|
int i; |
||||||
|
|
||||||
|
/* First, wait for the workers to finish. */ |
||||||
|
WaitForParallelWorkersToFinish(pei->pcxt); |
||||||
|
|
||||||
|
/* Next, accumulate buffer usage. */ |
||||||
|
for (i = 0; i < pei->pcxt->nworkers; ++i) |
||||||
|
InstrAccumParallelQuery(&pei->buffer_usage[i]); |
||||||
|
|
||||||
|
/* Finally, accumulate instrumentation, if any. */ |
||||||
|
if (pei->instrumentation) |
||||||
|
ExecParallelRetrieveInstrumentation(pei->planstate, |
||||||
|
pei->instrumentation); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* 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); |
||||||
|
} |
||||||
|
|
||||||
|
/*
|
||||||
|
* 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); |
||||||
|
ExecutorRun(queryDesc, ForwardScanDirection, 0L); |
||||||
|
ExecutorFinish(queryDesc); |
||||||
|
ExecutorEnd(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); |
||||||
|
|
||||||
|
/* Cleanup. */ |
||||||
|
FreeQueryDesc(queryDesc); |
||||||
|
(*receiver->rDestroy) (receiver); |
||||||
|
} |
||||||
@ -0,0 +1,36 @@ |
|||||||
|
/*--------------------------------------------------------------------
|
||||||
|
* execParallel.h |
||||||
|
* POSTGRES parallel execution interface |
||||||
|
* |
||||||
|
* Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group |
||||||
|
* Portions Copyright (c) 1994, Regents of the University of California |
||||||
|
* |
||||||
|
* IDENTIFICATION |
||||||
|
* src/include/executor/execParallel.h |
||||||
|
*-------------------------------------------------------------------- |
||||||
|
*/ |
||||||
|
|
||||||
|
#ifndef EXECPARALLEL_H |
||||||
|
#define EXECPARALLEL_H |
||||||
|
|
||||||
|
#include "access/parallel.h" |
||||||
|
#include "nodes/execnodes.h" |
||||||
|
#include "nodes/parsenodes.h" |
||||||
|
#include "nodes/plannodes.h" |
||||||
|
|
||||||
|
typedef struct SharedExecutorInstrumentation SharedExecutorInstrumentation; |
||||||
|
|
||||||
|
typedef struct ParallelExecutorInfo |
||||||
|
{ |
||||||
|
PlanState *planstate; |
||||||
|
ParallelContext *pcxt; |
||||||
|
BufferUsage *buffer_usage; |
||||||
|
SharedExecutorInstrumentation *instrumentation; |
||||||
|
shm_mq_handle **tqueue; |
||||||
|
} ParallelExecutorInfo; |
||||||
|
|
||||||
|
extern ParallelExecutorInfo *ExecInitParallelPlan(PlanState *planstate, |
||||||
|
EState *estate, int nworkers); |
||||||
|
extern void ExecParallelFinish(ParallelExecutorInfo *pei); |
||||||
|
|
||||||
|
#endif /* EXECPARALLEL_H */ |
||||||
Loading…
Reference in new issue