1 // Created on: 2005-03-15
2 // Created by: Peter KURNEV
3 // Copyright (c) 2005-2014 OPEN CASCADE SAS
5 // This file is part of Open CASCADE Technology software library.
7 // This library is free software; you can redistribute it and/or modify it under
8 // the terms of the GNU Lesser General Public License version 2.1 as published
9 // by the Free Software Foundation, with special exception defined in the file
10 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
11 // distribution for complete text of the license and disclaimer of any warranty.
13 // Alternatively, this file may be used under the terms of Open CASCADE
14 // commercial license or contractual agreement.
16 #include <Standard_MMgrOpt.hxx>
17 #include <Standard_OutOfMemory.hxx>
18 #include <Standard_Assert.hxx>
25 # include <sys/mman.h> /* mmap() */
30 #if defined (__sun) || defined(SOLARIS)
31 extern "C" int getpagesize() ;
34 //======================================================================
36 //======================================================================
38 // This implementation makes a number of assumptions regarding size of
41 // sizeof(Standard_Size) == sizeof(Standard_Address==void*)
43 // On WNT, sizeof(HANDLE) is equal of multiple of sizeof(Standard_Size)
45 //======================================================================
47 //======================================================================
49 // For clarity of implementation, the following conventions are used
50 // for naming variables:
52 // ...Size: size in bytes
54 // RoundSize, RSize etc.: size in bytes, rounded according to allocation granularity
56 // ...SizeN: size counted in number of items of sizeof(Standard_Size) bytes each
58 // ...Storage: address of the user area of the memory block (Standard_Address)
60 // ...Block: address of the hole memory block (header) (Standard_Size*)
62 //======================================================================
64 //======================================================================
67 // MMAP_BASE_ADDRESS, MMAP_FLAGS
68 #if defined (__hpux) || defined(HPUX)
69 #define MMAP_BASE_ADDRESS 0x80000000
70 #define MMAP_FLAGS (MAP_ANONYMOUS | MAP_PRIVATE | MAP_VARIABLE)
71 #elif defined (__osf__) || defined(DECOSF1)
72 #define MMAP_BASE_ADDRESS 0x1000000000
73 #define MMAP_FLAGS (MAP_ANONYMOUS | MAP_PRIVATE | MAP_VARIABLE)
75 #define MMAP_BASE_ADDRESS 0x80000000
76 #define MMAP_FLAGS (MAP_ANONYMOUS | MAP_PRIVATE | MAP_VARIABLE)
77 #elif defined(__APPLE__)
78 #define MMAP_BASE_ADDRESS 0x80000000
79 #define MMAP_FLAGS (MAP_ANON | MAP_PRIVATE)
81 #define MMAP_BASE_ADDRESS 0x20000000
82 #define MMAP_FLAGS (MAP_PRIVATE)
84 //static HANDLE myhMap;
86 #define MMAP_BASE_ADDRESS 0x60000000
87 #define MMAP_FLAGS (MAP_PRIVATE)
90 // Round size up to the specified page size
91 #define PAGE_ALIGN(size,thePageSize) \
92 (((size) + (thePageSize) - 1) & ~((thePageSize) - 1))
94 // Round size up to 4, 8, or 16 bytes
95 // Note that 0 yields 0
96 #define ROUNDUP16(size) (((size) + 0xf) & ~(Standard_Size)0xf)
97 #define ROUNDUP8(size) (((size) + 0x7) & ~(Standard_Size)0x7)
98 #define ROUNDUP4(size) (((size) + 0x3) & ~(Standard_Size)0x3)
99 #define ROUNDDOWN8(size) ((size) & ~(Standard_Size)0x7)
101 // The following two macros define granularity of memory allocation,
102 // by rounding size to the size of the allocation cell,
103 // and obtaining cell index from rounded size.
104 // Note that granularity shall be not less than sizeof(Standard_Size)
106 // Traditional implementation: granularity 16 bytes
107 //#define ROUNDUP_CELL(size) ROUNDUP16(size)
108 //#define INDEX_CELL(rsize) ((rsize) >> 4)
110 // Reduced granularity: 8 bytes
111 #define ROUNDUP_CELL(size) ROUNDUP8(size)
112 #define ROUNDDOWN_CELL(size) ROUNDDOWN8(size)
113 #define INDEX_CELL(rsize) ((rsize) >> 3)
115 /* In the allocated block, first bytes are used for storing of memory manager's data.
116 (size of block). The minimal size of these data is sizeof(int).
117 The memory allocated in system usually alligned by 16 bytes.Tthe aligment of the
118 data area in the memory block is shfted on BLOCK_SHIFT*sizeof(Standard_Size)
120 It is OK for WNT, SUN and Linux systems, but on SGI aligment should be 8 bytes.
121 So, BLOCK_SHIFT is formed as macro for support on other possible platforms.
124 #if defined(IRIX) || defined(SOLARIS)
125 #define BLOCK_SHIFT 2
127 #define BLOCK_SHIFT 1
130 // Get address of user area from block address, and vice-versa
131 #define GET_USER(block) (((Standard_Size*)(block)) + BLOCK_SHIFT)
132 #define GET_BLOCK(storage) (((Standard_Size*)(storage))-BLOCK_SHIFT)
134 // create static instance of out-of-memory exception to protect
135 // against possible lack of memory for its raising
136 static Handle(Standard_OutOfMemory) anOutOfMemError = new Standard_OutOfMemory;
138 //=======================================================================
139 //function : Standard_MMgr
141 //=======================================================================
143 Standard_MMgrOpt::Standard_MMgrOpt(const Standard_Boolean aClear,
144 const Standard_Boolean aMMap,
145 const Standard_Size aCellSize,
146 const Standard_Integer aNbPages,
147 const Standard_Size aThreshold)
149 // check basic assumption
150 Standard_STATIC_ASSERT(sizeof(Standard_Size) == sizeof(Standard_Address));
152 // clear buffer fields
160 // initialize parameters
162 myMMap = (Standard_Integer)aMMap;
163 myCellSize = aCellSize;
164 myNbPages = aNbPages;
165 myThreshold = aThreshold;
171 //=======================================================================
172 //function : ~Standard_MMgrOpt
174 //=======================================================================
176 Standard_MMgrOpt::~Standard_MMgrOpt()
178 Purge(Standard_True);
181 // NOTE: freeing pools may be dangerous if not all memory taken by
182 // this instance of the memory manager has been freed
188 //=======================================================================
189 //function : Initialize
191 //=======================================================================
193 void Standard_MMgrOpt::Initialize()
195 // check number of pages in small blocks pools
196 if ( myNbPages < 100 )
199 // get system-dependent page size
201 myPageSize = getpagesize();
205 SYSTEM_INFO SystemInfo;
206 GetSystemInfo (&SystemInfo);
207 myPageSize = SystemInfo.dwPageSize;
210 // initialize memory mapped files
212 #if defined (__sgi) || defined(IRIX)
213 /* Probleme de conflit en la zone des malloc et la zone des mmap sur SGI */
214 /* Ce probleme a ete identifie en IRIX 5.3 jusqu'en IRIX 6.2. Le probleme */
215 /* ne semble pas apparaitre en IRIX 6.4 */
216 /* Les malloc successifs donnent des adresses croissantes (a partir de 0x0x10000000) */
217 /* ce que l'on appelle le pointeur de BREAK */
218 /* Le premier mmap est force a l'addresse MMAP_BASE_ADDRESS (soit 0x60000000 sur SGI) */
219 /* mais les mmap suivants sont decides par le systeme (flag MAP_VARIABLE). Malheureusement */
220 /* il renvoie une addresse la plus basse possible dans la zone des malloc juste au dessus */
221 /* du BREAK soit 0x18640000 ce qui donne un espace d'allocation d'environ 140 Mo pour les */
222 /* malloc. Sur des gros modeles on peut avoir des pointes a 680 Mo en Rev6 pour une maquette */
223 /* de 2 000 000 de points. En Rev7, la meme maquette n'excedera pas 286 Mo (voir vision.for) */
224 /* Pour palier ce comportement, la solution adoptee est la suivante : */
225 /* Lorsque l'on entre dans alloc_startup (ici), on n'a pas encore fait de mmap. */
226 /* On fait alors un malloc (d'environ 700Mo) que l'on libere de suite. Cela a pour */
227 /* consequence de deplacer le BREAK tres haut. Le BREAK ne redescend jamais meme lors du free */
228 /* Le mmap donnant une adresse (environ 100 Mo au dessus du BREAK) on se retrouve alors avec */
229 /* le partage des zones de memoire suivant : */
230 /* 700 Mo pour les malloc - 500 Mo (1,2Go - 700Mo ) pour les mmap. Avec un CLD_SD_SIZE */
231 /* de 2 000 000 on atteind jamais 500 Mo de mmap, meme en chargeant des applications (qui */
232 /* utilisent la zone de mmap */
233 /* Ce partage des zones memoire pourra eventuellemt etre regle par une variable d'environnement */
236 Standard_Size high_sbrk;
238 high_sbrk = 700*1024*1024;
239 if ( (var=getenv("CLD_HIGH_SBRK")) != NULL ) {
240 high_sbrk = atoi(var);
243 var = (char*)malloc(high_sbrk); // 700 Mb
247 perror("ERR_MEMRY_FAIL");
250 #if defined(IRIX) || defined(__sgi) || defined(SOLARIS) || defined(__sun) || defined(LIN) || defined(linux) || defined(__FreeBSD__) || defined(__ANDROID__)
251 if ((myMMap = open ("/dev/zero", O_RDWR)) < 0) {
252 if ((myMMap = open ("/dev/null", O_RDWR)) < 0){
257 perror("ERR_MMAP_FAIL");
263 // initialize free lists
264 myFreeListMax = INDEX_CELL(ROUNDUP_CELL(myThreshold-BLOCK_SHIFT)); // all blocks less than myThreshold are to be recycled
265 myFreeList = (Standard_Size **) calloc (myFreeListMax+1, sizeof(Standard_Size *));
266 myCellSize = ROUNDUP16(myCellSize);
269 //=======================================================================
270 //function : SetMMgrOptCallBack
271 //purpose : Sets a callback function to be called on each alloc/free
272 //=======================================================================
274 static Standard_MMgrOpt::TPCallBackFunc MyPCallBackFunc = NULL;
276 Standard_EXPORT void Standard_MMgrOpt::SetCallBackFunction(TPCallBackFunc pFunc)
278 MyPCallBackFunc = pFunc;
281 inline void callBack(const Standard_Boolean isAlloc,
282 const Standard_Address aStorage,
283 const Standard_Size aRoundSize,
284 const Standard_Size aSize)
287 (*MyPCallBackFunc)(isAlloc, aStorage, aRoundSize, aSize);
290 //=======================================================================
291 //function : Allocate
293 //=======================================================================
295 Standard_Address Standard_MMgrOpt::Allocate(const Standard_Size aSize)
297 Standard_Size * aStorage = NULL;
299 // round up size according to allocation granularity
300 // The keyword 'volatile' is only used here for GCC 64-bit compilations
301 // otherwise this method would crash in runtime in optimized build.
302 volatile Standard_Size RoundSize = ROUNDUP_CELL(aSize);
303 const Standard_Size Index = INDEX_CELL(RoundSize);
305 // blocks of small and medium size are recyclable
306 if ( Index <= myFreeListMax ) {
307 const Standard_Size RoundSizeN = RoundSize / sizeof(Standard_Size);
309 // Lock access to critical data (myFreeList and other fields) by mutex.
310 // Note that we do not lock fields that do not change during the
311 // object life (such as myThreshold), and assume that calls to functions
312 // of standard library are already protected by their implementation.
313 // The unlock is called as soon as possible, for every treatment case.
314 // We also do not use Sentry, since in case if OCC signal or exception is
315 // caused by this block we will have deadlock anyway...
318 // if free block of the requested size is available, return it
319 if ( myFreeList[Index] ) {
320 // the address of the next free block is stored in the header
321 // of the memory block; use it to update list pointer
322 // to point to next free block
323 Standard_Size* aBlock = myFreeList[Index];
324 myFreeList[Index] = *(Standard_Size**)aBlock;
329 // record size of the allocated block in the block header and
330 // shift the pointer to the beginning of the user part of block
331 aBlock[0] = RoundSize;
332 aStorage = GET_USER(aBlock);
334 // clear block if requested
336 memset (aStorage, 0, RoundSize);
338 // else if block size is small allocate it in pools
339 else if ( RoundSize <= myCellSize ) {
340 // unlock the mutex for free lists
343 // and lock the specific mutex used to protect access to small blocks pools;
344 // note that this is done by sentry class so as to ensure unlocking in case of
345 // possible exception that may be thrown from AllocMemory()
346 Standard_Mutex::Sentry aSentry (myMutexPools);
348 // check for availability of requested space in the current pool
349 Standard_Size *aBlock = myNextAddr;
350 if ( &aBlock[ BLOCK_SHIFT+RoundSizeN] > myEndBlock ) {
351 // otherwise, allocate new memory pool with page-aligned size
352 Standard_Size Size = myPageSize * myNbPages;
353 aBlock = AllocMemory(Size); // note that size may be aligned by this call
355 if (myEndBlock > myNextAddr) {
356 // put the remaining piece to the free lists
357 const Standard_Size aPSize = (myEndBlock - GET_USER(myNextAddr))
358 * sizeof(Standard_Size);
359 const Standard_Size aRPSize = ROUNDDOWN_CELL(aPSize);
360 const Standard_Size aPIndex = INDEX_CELL(aRPSize);
361 if ( aPIndex > 0 && aPIndex <= myFreeListMax ) {
363 *(Standard_Size**)myNextAddr = myFreeList[aPIndex];
364 myFreeList[aPIndex] = myNextAddr;
369 // set end pointer to the end of the new pool
370 myEndBlock = aBlock + Size / sizeof(Standard_Size);
371 // record in the first bytes of the pool the address of the previous one
372 *(Standard_Size**)aBlock = myAllocList;
373 // and make new pool current (last)
374 // and get pointer to the first memory block in the pool
375 myAllocList = aBlock;
379 // initialize header of the new block by its size
380 // and get the pointer to the user part of block
381 aBlock[0] = RoundSize;
382 aStorage = GET_USER(aBlock);
384 // and advance pool pointer to the next free piece of pool
385 myNextAddr = &aStorage[RoundSizeN];
387 // blocks of medium size are allocated directly
389 // unlock the mutex immediately, as we do not need further to access any field
392 // we use operator ?: instead of if() since it is faster
393 Standard_Size *aBlock = (Standard_Size*) (myClear ? calloc( RoundSizeN+BLOCK_SHIFT, sizeof(Standard_Size)) :
394 malloc((RoundSizeN+BLOCK_SHIFT) * sizeof(Standard_Size)) );
396 // if allocation failed, try to free some memory by purging free lists, and retry
398 if ( Purge (Standard_False) )
399 aBlock = (Standard_Size*)calloc(RoundSizeN+BLOCK_SHIFT, sizeof(Standard_Size));
400 // if still not succeeded, raise exception
402 anOutOfMemError->Reraise ("Standard_MMgrOpt::Allocate(): malloc failed");
405 // initialize new block header by its size
406 // and get the pointer to the user part of block
407 aBlock[0] = RoundSize;
408 aStorage = GET_USER(aBlock);
411 // blocks of big size may be allocated as memory mapped files
413 // Compute size of the block to be allocated, including header,
414 // Note that we use rounded size, even if this block will not be stored in
415 // the free list, for consistency of calls to AllocMemory() / FreeMemory()
416 // and calculation of index in the free list
417 Standard_Size AllocSize = RoundSize + sizeof(Standard_Size);
420 Standard_Size* aBlock = AllocMemory(AllocSize);
422 // initialize new block header by its size
423 // and get the pointer to the user part of block.
424 aBlock[0] = RoundSize;
425 aStorage = GET_USER(aBlock);
428 callBack(Standard_True, aStorage, RoundSize, aSize);
433 //=======================================================================
436 //=======================================================================
438 void Standard_MMgrOpt::Free(Standard_Address theStorage)
440 // safely return if attempt to free null pointer
444 // get the pointer to the memory block header
445 Standard_Size* aBlock = GET_BLOCK(theStorage);
447 // and get the allocated size of the block
448 Standard_Size RoundSize = aBlock[0];
450 callBack(Standard_False, theStorage, RoundSize, 0);
452 // check whether blocks with that size are recyclable
453 const Standard_Size Index = INDEX_CELL(RoundSize);
454 if ( Index <= myFreeListMax ) {
455 // Lock access to critical data (myFreeList and other) by mutex
456 // Note that we do not lock fields that do not change during the
457 // object life (such as myThreshold), and assume that calls to functions
458 // of standard library are already protected by their implementation.
459 // We also do not use Sentry, since in case if OCC signal or exception is
460 // caused by this block we will have deadlock anyway...
463 // in the memory block header, record address of the next free block
464 *(Standard_Size**)aBlock = myFreeList[Index];
465 // add new block to be first in the list
466 myFreeList[Index] = aBlock;
470 // otherwise, we have block of big size which shall be simply released
472 FreeMemory (aBlock, RoundSize);
475 //=======================================================================
477 //purpose : Frees all free lists except small blocks (less than CellSize)
478 //=======================================================================
480 Standard_Integer Standard_MMgrOpt::Purge(Standard_Boolean )
482 // Lock access to critical data by mutex
483 Standard_Mutex::Sentry aSentry (myMutex);
485 // TODO: implement support for isDeleted = True
487 // free memory blocks contained in free lists
488 // whose sizes are greater than cellsize
489 Standard_Integer nbFreed = 0;
490 Standard_Size i = INDEX_CELL(ROUNDUP_CELL(myCellSize+BLOCK_SHIFT));
491 for (; i <= myFreeListMax; i++ ) {
492 Standard_Size * aFree = myFreeList[i];
494 Standard_Size * anOther = aFree;
495 aFree = * (Standard_Size **) aFree;
499 myFreeList[i] = NULL;
502 // Lock access to critical data by mutex
503 Standard_Mutex::Sentry aSentry1 (myMutexPools);
505 // release memory pools containing no busy memory;
506 // for that for each pool count the summary size of blocks
507 // got from the free lists allocated from this pool
509 const Standard_Size PoolSize = myPageSize * myNbPages;
511 const Standard_Size PoolSize =
512 PAGE_ALIGN(myPageSize * myNbPages + sizeof(HANDLE), myPageSize) -
515 const Standard_Size RPoolSize = ROUNDDOWN_CELL(PoolSize);
516 const Standard_Size PoolSizeN = RPoolSize / sizeof(Standard_Size);
518 // declare the table of pools;
519 // (we map free blocks onto a number of pools simultaneously)
520 static const Standard_Integer NB_POOLS_WIN = 512;
521 static Standard_Size* aPools[NB_POOLS_WIN];
522 static Standard_Size aFreeSize[NB_POOLS_WIN];
523 static Standard_Integer aFreePools[NB_POOLS_WIN];
525 Standard_Size * aNextPool = myAllocList;
526 Standard_Size * aPrevPool = NULL;
527 const Standard_Size nCells = INDEX_CELL(myCellSize);
528 Standard_Integer nPool = 0, nPoolFreed = 0;
531 // fill the table of pools
532 Standard_Integer iPool;
533 for (iPool = 0; aNextPool && iPool < NB_POOLS_WIN; iPool++) {
534 aPools[iPool] = aNextPool;
535 aFreeSize[iPool] = 0;
536 aNextPool = * (Standard_Size **) aNextPool; // get next pool
538 const Standard_Integer iLast = iPool - 1;
541 // scan free blocks, find corresponding pools and increment
543 for (i = 0; i <= nCells; i++ ) {
544 Standard_Size * aFree = myFreeList[i];
545 Standard_Size aSize = BLOCK_SHIFT * sizeof(Standard_Size) +
548 for (iPool = 0; iPool <= iLast; iPool++) {
549 if (aFree >= aPools[iPool] && aFree < aPools[iPool] + PoolSizeN) {
550 aFreeSize[iPool] += aSize;
554 aFree = * (Standard_Size **) aFree; // get next free block
558 // scan the table and make the list of free pools
559 Standard_Integer iLastFree = -1;
560 for (iPool = 0; iPool <= iLast; iPool++) {
561 aFreeSize[iPool] = ROUNDUP_CELL(aFreeSize[iPool]);
562 if (aFreeSize[iPool] == RPoolSize)
563 aFreePools[++iLastFree] = iPool;
565 if (iLastFree == -1) {
566 // no free pools found in this table
567 aPrevPool = aPools[iLast];
571 // scan free blocks again, and remove those of them
572 // that belong to free pools
574 for (i = 0; i <= nCells; i++ ) {
575 Standard_Size * aFree = myFreeList[i];
576 Standard_Size * aPrevFree = NULL;
578 for (j = 0; j <= iLastFree; j++) {
579 iPool = aFreePools[j];
580 if (aFree >= aPools[iPool] && aFree < aPools[iPool] + PoolSizeN)
586 aFree = * (Standard_Size **) aFree;
588 * (Standard_Size **) aPrevFree = aFree; // link to previous
590 myFreeList[i] = aFree;
596 aFree = * (Standard_Size **) aFree;
601 // release free pools, and reconnect remaining pools
602 // in the linked list
603 Standard_Size * aPrev = (aFreePools[0] == 0
605 : aPools[aFreePools[0] - 1]);
606 for (j = 0; j <= iLastFree; j++) {
607 iPool = aFreePools[j];
609 // update the pointer to the previous non-free pool
610 if (iPool - aFreePools[j - 1] > 1)
611 aPrev = aPools[iPool - 1];
613 if (j == iLastFree || aFreePools[j + 1] - iPool > 1) {
614 // get next non-free pool
615 Standard_Size * aNext =
616 (j == iLastFree && aFreePools[j] == iLast)
619 // and connect it to the list of pools that have been processed
620 // and remain non-free
622 * (Standard_Size **) aPrev = aNext;
626 FreeMemory(aPools[iPool], PoolSize);
628 // update the pointer to the previous non-free pool
629 aPrevPool = (aFreePools[iLastFree] == iLast
632 nPoolFreed += iLastFree + 1;
638 //=======================================================================
639 //function : FreePools
640 //purpose : Frees all memory pools allocated for small blocks
641 //=======================================================================
643 void Standard_MMgrOpt::FreePools()
645 // Lock access to critical data by mutex
646 Standard_Mutex::Sentry aSentry (myMutexPools);
648 // last pool is remembered in myAllocList
649 Standard_Size * aFree = myAllocList;
652 Standard_Size * aBlock = aFree;
653 // next pool address is stored in first 8 bytes of each pool
654 aFree = * (Standard_Size **) aFree;
655 // free pool (note that its size is calculated rather than stored)
656 FreeMemory ( aBlock, myPageSize * myNbPages );
660 //=======================================================================
661 //function : Reallocate
663 //=======================================================================
665 Standard_Address Standard_MMgrOpt::Reallocate(Standard_Address theStorage,
666 const Standard_Size theNewSize)
668 // if theStorage == NULL, just allocate new memory block
671 return Allocate(theNewSize);
674 Standard_Size * aBlock = GET_BLOCK(theStorage);
675 Standard_Address newStorage = NULL;
677 // get current size of the memory block from its header
678 Standard_Size OldSize = aBlock[0];
680 // if new size is less than old one, just do nothing
681 if (theNewSize <= OldSize) {
682 newStorage = theStorage;
684 // otherwise, allocate new block and copy the data to it
686 newStorage = Allocate(theNewSize);
687 memcpy (newStorage, theStorage, OldSize);
689 // clear newly added part of the block
691 memset(((char*)newStorage) + OldSize, 0, theNewSize-OldSize);
696 //=======================================================================
697 //function : AllocMemory
698 //purpose : Allocate a big block of memory using either malloc/calloc
699 // or memory mapped file
700 //=======================================================================
702 Standard_Size * Standard_MMgrOpt::AllocMemory(Standard_Size &Size)
704 // goto is used as efficient method for a possibility to retry allocation
707 Standard_Size * aBlock = NULL;
709 // if MMap option is ON, allocate using memory mapped files
713 // align size to page size
714 const Standard_Size AlignedSize = PAGE_ALIGN(Size, myPageSize);
717 // note that on UNIX myMMap is file descriptor for /dev/null
718 aBlock = (Standard_Size * )mmap((char*)MMAP_BASE_ADDRESS, AlignedSize,
719 PROT_READ | PROT_WRITE, MMAP_FLAGS,
721 if (aBlock == MAP_FAILED /* -1 */) {
723 // as a last resort, try freeing some memory by calling Purge()
724 if ( Purge(Standard_False) )
726 // if nothing helps, raise exception
727 anOutOfMemError->Reraise (strerror(errcode));
730 // save actually allocated size into argument
735 // align size to page size, taking into account additional space needed to
736 // store handle to the memory map
737 const Standard_Size AlignedSize = PAGE_ALIGN(Size+sizeof(HANDLE), myPageSize);
739 // allocate mapped file
740 HANDLE hMap = CreateFileMapping(INVALID_HANDLE_VALUE, NULL,
742 DWORD(AlignedSize / 0x80000000),
743 DWORD(AlignedSize % 0x80000000), NULL);
744 HANDLE * aMBlock = (hMap && GetLastError() != ERROR_ALREADY_EXISTS ?
745 (HANDLE*)MapViewOfFile(hMap,FILE_MAP_WRITE,0,0,0) : NULL);
746 // check for error and try allocating address space
749 // close handle if allocated
753 // as a last resort, try freeing some memory by calling Purge() and retry
754 if ( Purge(Standard_False) )
756 // if nothing helps, make error message and raise exception
757 const int BUFSIZE=1024;
758 char message[BUFSIZE];
759 if ( FormatMessage (FORMAT_MESSAGE_FROM_SYSTEM, 0, GetLastError(), 0, message, BUFSIZE-1, 0) <=0 )
760 strcpy (message, "Standard_MMgrOpt::AllocMemory() failed to mmap");
761 anOutOfMemError->Reraise (message);
764 // record map handle in the beginning
767 // and shift to the beginning of usable area
768 aBlock = (Standard_Size*)(aMBlock+1);
770 // save actually allocated size into argument
771 Size = AlignedSize - sizeof(HANDLE);
774 // else just allocate by malloc or calloc
776 aBlock = (Standard_Size *) (myClear ? calloc(Size,sizeof(char)) : malloc(Size));
780 // as a last resort, try freeing some memory by calling Purge()
781 if ( Purge(Standard_False) )
783 // if nothing helps, raise exception
784 anOutOfMemError->Reraise ("Standard_MMgrOpt::Allocate(): malloc failed");
787 // clear whole block if clearing option is set
789 memset (aBlock, 0, Size);
793 //=======================================================================
794 //function : FreeMemory
796 //=======================================================================
798 void Standard_MMgrOpt::FreeMemory (Standard_Address aBlock,
805 // release memory (either free or unmap)
808 // align size to page size, just the same as in AllocMemory()
809 const Standard_Size AlignedSize = PAGE_ALIGN(aSize, myPageSize);
810 munmap((char*)aBlock, AlignedSize);
812 // recover handle to the memory mapping stored just before the block
813 const HANDLE * aMBlock = (const HANDLE *)aBlock;
814 HANDLE hMap = *(--aMBlock);
815 UnmapViewOfFile((LPCVOID)aMBlock);