Added ability to control memory consumption between request using ZEND_MM_COMPACT environment variable

NEWS

@@ -1,6 +1,8 @@
 PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2007, PHP 5.2.5RC2
+- Added ability to control memory consumption between request using
+  ZEND_MM_COMPACT environment variable. (Dmitry)
 
 18 Oct 2007, PHP 5.2.5RC1
 - Upgraded PCRE to version 7.3 (Nuno)

Zend/zend_alloc.c

@@ -396,6 +396,7 @@ struct _zend_mm_heap {
 	size_t              free_bitmap;
 	size_t              large_free_bitmap;
 	size_t              block_size;
+	size_t              compact_size;
 	zend_mm_segment    *segments_list;
 	zend_mm_storage    *storage;
 	size_t				real_size;
@@ -1028,6 +1029,7 @@ ZEND_API zend_mm_heap *zend_mm_startup_ex(const zend_mm_mem_handlers *handlers,
 
 	heap->storage = storage;
 	heap->block_size = block_size;
+	heap->compact_size = 0;
 	heap->segments_list = NULL;
 	zend_mm_init(heap);
 # if ZEND_MM_CACHE_STAT
@@ -1078,6 +1080,7 @@ ZEND_API zend_mm_heap *zend_mm_startup(void)
 	char *mem_type = getenv("ZEND_MM_MEM_TYPE");
 	char *tmp;
 	const zend_mm_mem_handlers *handlers;
+	zend_mm_heap *heap;
 
 	if (mem_type == NULL) {
 		i = 0;
@@ -1109,7 +1112,16 @@ ZEND_API zend_mm_heap *zend_mm_startup(void)
 		seg_size = ZEND_MM_SEG_SIZE;
 	}
 
-	return zend_mm_startup_ex(handlers, seg_size, ZEND_MM_RESERVE_SIZE, 0, NULL);
+	heap = zend_mm_startup_ex(handlers, seg_size, ZEND_MM_RESERVE_SIZE, 0, NULL);
+	if (heap) {
+		tmp = getenv("ZEND_MM_COMPACT");
+		if (tmp) {
+			heap->compact_size = zend_atoi(tmp, 0);
+		} else {
+			heap->compact_size = 2 * 1024 * 1024;
+		}
+	}
+	return heap;
 }
 
 #if ZEND_DEBUG
@@ -1563,7 +1575,9 @@ ZEND_API void zend_mm_shutdown(zend_mm_heap *heap, int full_shutdown, int silent
 #ifdef HAVE_MEM_WIN32
 		/* FIX for bug #41713 */
 		/* TODO: add new "compact" handler */
-		if (storage->handlers->dtor == zend_mm_mem_win32_dtor &&
+		if (heap->compact_size &&
+		    heap->real_peak > heap->compact_size &&
+		    storage->handlers->dtor == zend_mm_mem_win32_dtor &&
 		    storage->handlers->init == zend_mm_mem_win32_init) {
 		    HeapDestroy((HANDLE)storage->data);
 		    storage->data = (void*)HeapCreate(HEAP_NO_SERIALIZE, 0, 0);