granicus.if.org Git - postgresql/blob - src/backend/storage/ipc/ipci.c

   1 /*-------------------------------------------------------------------------
   2  *
   3  * ipci.c
   4  *        POSTGRES inter-process communication initialization code.
   5  *
   6  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  *
  10  * IDENTIFICATION
  11  *        $Header: /cvsroot/pgsql/src/backend/storage/ipc/ipci.c,v 1.45 2001/11/04 19:55:31 tgl Exp $
  12  *
  13  *-------------------------------------------------------------------------
  14  */
  15 #include "postgres.h"
  16
  17 #include <sys/types.h>
  18
  19 #include "miscadmin.h"
  20 #include "access/clog.h"
  21 #include "access/xlog.h"
  22 #include "storage/bufmgr.h"
  23 #include "storage/freespace.h"
  24 #include "storage/lmgr.h"
  25 #include "storage/lwlock.h"
  26 #include "storage/pmsignal.h"
  27 #include "storage/proc.h"
  28 #include "storage/sinval.h"
  29 #include "storage/spin.h"
  30
  31
  32 /*
  33  * CreateSharedMemoryAndSemaphores
  34  *              Creates and initializes shared memory and semaphores.
  35  *
  36  * This is called by the postmaster or by a standalone backend.
  37  * It is NEVER called by a backend forked from the postmaster;
  38  * for such a backend, the shared memory is already ready-to-go.
  39  *
  40  * If "makePrivate" is true then we only need private memory, not shared
  41  * memory.      This is true for a standalone backend, false for a postmaster.
  42  */
  43 void
  44 CreateSharedMemoryAndSemaphores(bool makePrivate, int maxBackends)
  45 {
  46         int                     size;
  47         PGShmemHeader *seghdr;
  48
  49         /*
  50          * Size of the Postgres shared-memory block is estimated via
  51          * moderately-accurate estimates for the big hogs, plus 100K for the
  52          * stuff that's too small to bother with estimating.
  53          */
  54         size = BufferShmemSize();
  55         size += LockShmemSize(maxBackends);
  56         size += XLOGShmemSize();
  57         size += CLOGShmemSize();
  58         size += LWLockShmemSize();
  59         size += SInvalShmemSize(maxBackends);
  60         size += FreeSpaceShmemSize();
  61 #ifdef STABLE_MEMORY_STORAGE
  62         size += MMShmemSize();
  63 #endif
  64         size += 100000;
  65         /* might as well round it off to a multiple of a typical page size */
  66         size += 8192 - (size % 8192);
  67
  68         if (DebugLvl > 1)
  69                 fprintf(stderr, "invoking IpcMemoryCreate(size=%d)\n", size);
  70
  71         /*
  72          * Create the shmem segment
  73          */
  74         seghdr = IpcMemoryCreate(size, makePrivate, IPCProtection);
  75
  76         /*
  77          * First initialize spinlocks --- needed by InitShmemAllocation()
  78          */
  79         CreateSpinlocks();
  80
  81         /*
  82          * Set up shared memory allocation mechanism
  83          */
  84         InitShmemAllocation(seghdr);
  85
  86         /*
  87          * Now initialize LWLocks, which do shared memory allocation and are
  88          * needed for InitShmemIndex.
  89          */
  90         CreateLWLocks();
  91
  92         /*
  93          * Set up shmem.c index hashtable
  94          */
  95         InitShmemIndex();
  96
  97         /*
  98          * Set up xlog, clog, and buffers
  99          */
 100         XLOGShmemInit();
 101         CLOGShmemInit();
 102         InitBufferPool();
 103
 104         /*
 105          * Set up lock manager
 106          */
 107         InitLocks();
 108         if (InitLockTable(maxBackends) == INVALID_TABLEID)
 109                 elog(FATAL, "Couldn't create the lock table");
 110
 111         /*
 112          * Set up process table
 113          */
 114         InitProcGlobal(maxBackends);
 115
 116         /*
 117          * Set up shared-inval messaging
 118          */
 119         CreateSharedInvalidationState(maxBackends);
 120
 121         /*
 122          * Set up free-space map
 123          */
 124         InitFreeSpaceMap();
 125
 126         /*
 127          * Set up child-to-postmaster signaling mechanism
 128          */
 129         PMSignalInit();
 130 }