src/bin/pg_dump/parallel.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * parallel.h
   4  *
   5  *      Parallel support for pg_dump and pg_restore
   6  *
   7  * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * IDENTIFICATION
  11  *              src/bin/pg_dump/parallel.h
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15
  16 #ifndef PG_DUMP_PARALLEL_H
  17 #define PG_DUMP_PARALLEL_H
  18
  19 #include <limits.h>
  20
  21 #include "pg_backup_archiver.h"
  22
  23 /* Function to call in leader process on completion of a worker task */
  24 typedef void (*ParallelCompletionPtr) (ArchiveHandle *AH,
  25                                                                            TocEntry *te,
  26                                                                            int status,
  27                                                                            void *callback_data);
  28
  29 /* Wait options for WaitForWorkers */
  30 typedef enum
  31 {
  32         WFW_NO_WAIT,
  33         WFW_GOT_STATUS,
  34         WFW_ONE_IDLE,
  35         WFW_ALL_IDLE,
  36 } WFW_WaitOption;
  37
  38 /*
  39  * Maximum number of parallel jobs allowed.
  40  *
  41  * On Windows we can only have at most MAXIMUM_WAIT_OBJECTS (= 64 usually)
  42  * parallel jobs because that's the maximum limit for the
  43  * WaitForMultipleObjects() call.
  44  */
  45 #ifdef WIN32
  46 #define PG_MAX_JOBS MAXIMUM_WAIT_OBJECTS
  47 #else
  48 #define PG_MAX_JOBS INT_MAX
  49 #endif
  50
  51 /* ParallelSlot is an opaque struct known only within parallel.c */
  52 typedef struct ParallelSlot ParallelSlot;
  53
  54 /* Overall state for parallel.c */
  55 typedef struct ParallelState
  56 {
  57         int                     numWorkers;             /* allowed number of workers */
  58         /* these arrays have numWorkers entries, one per worker: */
  59         TocEntry  **te;                         /* item being worked on, or NULL */
  60         ParallelSlot *parallelSlot; /* private info about each worker */
  61 } ParallelState;
  62
  63 #ifdef WIN32
  64 extern bool parallel_init_done;
  65 extern DWORD mainThreadId;
  66 #endif
  67
  68 extern void init_parallel_dump_utils(void);
  69
  70 extern bool IsEveryWorkerIdle(ParallelState *pstate);
  71 extern void WaitForWorkers(ArchiveHandle *AH, ParallelState *pstate,
  72                                                    WFW_WaitOption mode);
  73
  74 extern ParallelState *ParallelBackupStart(ArchiveHandle *AH);
  75 extern void DispatchJobForTocEntry(ArchiveHandle *AH,
  76                                                                    ParallelState *pstate,
  77                                                                    TocEntry *te,
  78                                                                    T_Action act,
  79                                                                    ParallelCompletionPtr callback,
  80                                                                    void *callback_data);
  81 extern void ParallelBackupEnd(ArchiveHandle *AH, ParallelState *pstate);
  82
  83 extern void set_archive_cancel_info(ArchiveHandle *AH, PGconn *conn);
  84
  85 #endif                                                  /* PG_DUMP_PARALLEL_H */