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Overview
Comment:New simplified memory initialization for MacOS.
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Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA3-256: 055b36f1c1593bb123f7319a07c476143d71af052b5b8d34afcd0d500f197882
User & Date: drh 2017-03-21 20:17:24.121
Context
2017-03-22
21:24
Initial implementation of the json_mergepatch(A,B) SQL function. (check-in: a267444039 user: drh tags: json_mergepatch)
12:51
Fix harmless compiler warnings in the shell. (check-in: a786829783 user: drh tags: trunk)
2017-03-21
20:17
New simplified memory initialization for MacOS. (check-in: 055b36f1c1 user: drh tags: trunk)
18:56
Fix an incorrect assert in the ANALYZE logic for STAT4 on WITHOUT ROWID tables. (check-in: ad741976c8 user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/mem1.c.
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}

/*
** Initialize this module.
*/
static int sqlite3MemInit(void *NotUsed){
#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)


  if( _sqliteZone_ ){
    return SQLITE_OK;
  }
#ifndef SQLITE_MIGHT_BE_SINGLE_CORE
  /* If not compiled with the SQLITE_MIGHT_BE_SINGLE_CORE flag, assume
  ** that multiple cores are always available.  This is the default case.
  */
  _sqliteZone_ = malloc_default_zone();
#else
  /* With the SQLITE_MIGHT_BE_SINGLE_CORE compile-time option, check the
  ** number of cores.  Different malloc() strategies are used for single-core and
  ** multi-core machines.
  */
  {
    int cpuCount;
    size_t len;
    len = sizeof(cpuCount);
    /* One usually wants to use hw.acctivecpu for MT decisions, but not here */
    sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0);
    if( cpuCount>1 ){
      /* defer MT decisions to system malloc */
      _sqliteZone_ = malloc_default_zone();
    }else{
      /* only 1 core, use our own zone to contention over global locks, 
      ** e.g. we have our own dedicated locks */
      bool success;
      malloc_zone_t* newzone = malloc_create_zone(4096, 0);
      malloc_set_zone_name(newzone, "Sqlite_Heap");
      do{
        success = OSAtomicCompareAndSwapPtrBarrier(NULL, newzone, 
                                   (void * volatile *)&_sqliteZone_);
      }while(!_sqliteZone_);
      if( !success ){
        /* somebody registered a zone first */
        malloc_destroy_zone(newzone);
      }
    }
  }
#endif /* SQLITE_MIGHT_BE_SINGLE_CORE */
#endif /*  defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC) */
  UNUSED_PARAMETER(NotUsed);
  return SQLITE_OK;
}

/*
** Deinitialize this module.








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}

/*
** Initialize this module.
*/
static int sqlite3MemInit(void *NotUsed){
#if defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC)
  int cpuCount;
  size_t len;
  if( _sqliteZone_ ){
    return SQLITE_OK;
  }













  len = sizeof(cpuCount);
  /* One usually wants to use hw.acctivecpu for MT decisions, but not here */
  sysctlbyname("hw.ncpu", &cpuCount, &len, NULL, 0);
  if( cpuCount>1 ){
    /* defer MT decisions to system malloc */
    _sqliteZone_ = malloc_default_zone();
  }else{
    /* only 1 core, use our own zone to contention over global locks, 
    ** e.g. we have our own dedicated locks */

    _sqliteZone_ = malloc_create_zone(4096, 0);
    malloc_set_zone_name(_sqliteZone_, "Sqlite_Heap");







  }



#endif /*  defined(__APPLE__) && !defined(SQLITE_WITHOUT_ZONEMALLOC) */
  UNUSED_PARAMETER(NotUsed);
  return SQLITE_OK;
}

/*
** Deinitialize this module.
︙︙