i2p/haiku-beta6
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

* The system now holds back a small reserve of committable memory and pages. The

Browse Source 
memory and page reservation functions have a new "priority" parameter that
  indicates how deep the function may tap into that reserve. The currently
  existing priority levels are "user", "system", and "VIP". The idea is that
  user programs should never be able to cause a state that gets the kernel into
  trouble due to heavy battling for memory. The "VIP" level (not really used
  yet) is intended for allocations that are required to free memory eventually
  (in the page writer). More levels are thinkable in the future, like "user real
  time" or "user system server".
* Added "priority" parameters to several VMCache methods.
* Replaced the map_backing_store() "unmapAddressRange" parameter by a "flags"
  parameter.
* Added area creation flag CREATE_AREA_PRIORITY_VIP and slab allocator flag
  CACHE_PRIORITY_VIP indicating the importance of the request.
* Changed most code to pass the right priorities/flags.

These changes already significantly improve the behavior in low memory
situations. I've tested a bit with 64 MB (virtual) RAM and, while not
particularly fast and responsive, the system remains at least usable under high
memory pressure.
As a side effect the slab allocator can now be used as general memory allocator.
Not done by default yet, though.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35295 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Ingo Weinhold
2010-01-26 14:44:58 +00:00
parent c5d6e9b06e
commit cff6e9e406
19 changed files with 351 additions and 118 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/system/kernel/slab/MemoryManager.cpp
+9 -4
View File
@@ -1181,8 +1181,11 @@ MemoryManager::_AllocateArea(uint32 flags, Area*& _area)
if (sKernelArgs == NULL) {
// create an area
uint32 areaCreationFlags = (flags & CACHE_PRIORITY_VIP) != 0
? CREATE_AREA_PRIORITY_VIP : 0;
area_id areaID = vm_create_null_area(B_SYSTEM_TEAM, kSlabAreaName,
(void**)&area, B_ANY_KERNEL_BLOCK_ADDRESS, SLAB_AREA_SIZE);
(void**)&area, B_ANY_KERNEL_BLOCK_ADDRESS, SLAB_AREA_SIZE,
areaCreationFlags);
if (areaID < 0) {
mutex_lock(&sLock);
return areaID;
@@ -1315,8 +1318,10 @@ MemoryManager::_MapChunk(VMArea* vmArea, addr_t address, size_t size,
VMTranslationMap* translationMap = addressSpace->TranslationMap();
// reserve memory for the chunk
int priority = (flags & CACHE_PRIORITY_VIP) != 0
? VM_PRIORITY_VIP : VM_PRIORITY_SYSTEM;
size_t reservedMemory = size + reserveAdditionalMemory;
status_t error = vm_try_reserve_memory(size,
status_t error = vm_try_reserve_memory(size, priority,
(flags & CACHE_DONT_WAIT_FOR_MEMORY) != 0 ? 0 : 1000000);
if (error != B_OK)
return error;
@@ -1325,12 +1330,12 @@ MemoryManager::_MapChunk(VMArea* vmArea, addr_t address, size_t size,
size_t reservedPages = size / B_PAGE_SIZE
+ translationMap->MaxPagesNeededToMap(address, address + size - 1);
if ((flags & CACHE_DONT_WAIT_FOR_MEMORY) != 0) {
if (!vm_page_try_reserve_pages(reservedPages)) {
if (!vm_page_try_reserve_pages(reservedPages, priority)) {
vm_unreserve_memory(reservedMemory);
return B_WOULD_BLOCK;
}
} else
vm_page_reserve_pages(reservedPages);
vm_page_reserve_pages(reservedPages, priority);
VMCache* cache = vm_area_get_locked_cache(vmArea);