Alexandre Julliard : ntdll: Increase subheap size quadratically to avoid slowdown when allocating tons of heap memory .

[Alexandre Julliard]

Module: wine
Branch: master
Commit: c38ce28af574b60e0ca0733d88a85c53e35082ad
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=c38ce28af574b60e0ca0733d88...

Author: Alexandre Julliard 
Date:   Tue Nov 18 12:49:12 2008 +0100

ntdll: Increase subheap size quadratically to avoid slowdown when allocating tons of heap memory.

---

dlls/ntdll/heap.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/dlls/ntdll/heap.c b/dlls/ntdll/heap.c
index d94e1f0..99a68d2 100644
--- a/dlls/ntdll/heap.c
+++ b/dlls/ntdll/heap.c
@@ -142,9 +142,10 @@ typedef struct tagHEAP
     struct list      entry;         /* Entry in process heap list */
     struct list      subheap_list;  /* Sub-heap list */
     struct list      large_list;    /* Large blocks list */
+    SIZE_T           grow_size;     /* Size of next subheap for growing heap */
     DWORD            magic;         /* Magic number */
     RTL_CRITICAL_SECTION critSection; /* Critical section for serialization */
-    FREE_LIST_ENTRY  freeList[HEAP_NB_FREE_LISTS];  /* Free lists */
+    FREE_LIST_ENTRY  freeList[HEAP_NB_FREE_LISTS] DECLSPEC_ALIGN(8);  /* Free lists */
 } HEAP;

#define HEAP_MAGIC       ((DWORD)('H' | ('E'<<8) | ('A'<<16) | ('P'<<24)))
@@ -808,6 +809,7 @@ static SUBHEAP *HEAP_CreateSubHeap( HEAP *heap, LPVOID address, DWORD flags,
         heap = (HEAP *)address;
         heap->flags         = flags;
         heap->magic         = HEAP_MAGIC;
+        heap->grow_size     = max( HEAP_DEF_SIZE, totalSize );
         list_init( &heap->subheap_list );
         list_init( &heap->large_list );

@@ -918,11 +920,13 @@ static ARENA_FREE *HEAP_FindFreeBlock( HEAP *heap, SIZE_T size,
     if (total_size < size) return NULL;  /* overflow */

if (!(subheap = HEAP_CreateSubHeap( heap, NULL, heap->flags, total_size,
-                                        max( HEAP_DEF_SIZE, total_size ) )))
+                                        max( heap->grow_size, total_size ) )))
         return NULL;

+    if (heap->grow_size < 128 * 1024 * 1024) heap->grow_size *= 2;
+
     TRACE("created new sub-heap %p of %08lx bytes for heap %p\n",
-            subheap, total_size, heap );
+          subheap, subheap->size, heap );

*ppSubHeap = subheap;
     return (ARENA_FREE *)((char *)subheap->base + subheap->headerSize);