Quelle  execParallel.h

/*--------------------------------------------------------------------
 * execParallel.h
 *  POSTGRES parallel execution interface
 *
 * Portions Copyright (c) 1996-2025, 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"
#include "utils/dsa.h"

typedef struct SharedExecutorInstrumentation SharedExecutorInstrumentation;

typedef struct ParallelExecutorInfo
{
 PlanState  *planstate;  /* plan subtree we're running in parallel */
 ParallelContext *pcxt;  /* parallel context we're using */
 BufferUsage *buffer_usage; /* points to bufusage area in DSM */
 WalUsage   *wal_usage;  /* walusage area in DSM */
 SharedExecutorInstrumentation *instrumentation; /* optional */
 struct SharedJitInstrumentation *jit_instrumentation; /* optional */
 dsa_area   *area;   /* points to DSA area in DSM */
 dsa_pointer param_exec;  /* serialized PARAM_EXEC parameters */
 bool  finished;  /* set true by ExecParallelFinish */
 /* These two arrays have pcxt->nworkers_launched entries: */
 shm_mq_handle **tqueue;  /* tuple queues for worker output */
 struct TupleQueueReader **reader; /* tuple reader/writer support */
} ParallelExecutorInfo;

extern ParallelExecutorInfo *ExecInitParallelPlan(PlanState *planstate,
              EState *estate, Bitmapset *sendParams, int nworkers,
              int64 tuples_needed);
extern void ExecParallelCreateReaders(ParallelExecutorInfo *pei);
extern void ExecParallelFinish(ParallelExecutorInfo *pei);
extern void ExecParallelCleanup(ParallelExecutorInfo *pei);
extern void ExecParallelReinitialize(PlanState *planstate,
          ParallelExecutorInfo *pei, Bitmapset *sendParams);

extern void ParallelQueryMain(dsm_segment *seg, shm_toc *toc);

#endif       /* EXECPARALLEL_H */