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The page thief can now also steal active pages under pressure.

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git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@22456 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Axel Dörfler 2007-10-06 11:38:03 +00:00
parent 0e18334057
commit 1211351476
1 changed files with 9 additions and 10 deletions
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19
src/system/kernel/vm/vm_page.cpp
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@ -760,7 +760,7 @@ page_thief(void* /*unused*/)
//dprintf("page thief running - target %ld...\n", steal);
vm_page* page = NULL;
bool stealActive = false;
bool stealActive = false, desperate = false;
InterruptsSpinLocker locker(sPageLock);
while (steal > 0) {
@ -790,9 +790,10 @@ page_thief(void* /*unused*/)
break;
// when memory is really low, we really want pages
if (stealActive)
if (stealActive) {
score = 127;
else {
desperate = true;
} else {
stealActive = true;
score = 5;
steal = 5;
@ -841,13 +842,11 @@ page_thief(void* /*unused*/)
if (!cacheLocker.IsLocked())
continue;
if (page->state != PAGE_STATE_INACTIVE) {
// TODO: if this is an active page (as in stealActive), we need
// to unmap it and check if it's modified in an atomic operation.
// For now, we'll just ignore it, even though this might let
// vm_page_allocate_page() wait forever...
// check again if that page is still a candidate
if (page->state != PAGE_STATE_INACTIVE
&& (!stealActive || page->state != PAGE_STATE_ACTIVE
|| page->wired_count != 0))
continue;
}
// recheck eventual last minute changes
uint32 flags;
@ -856,7 +855,7 @@ page_thief(void* /*unused*/)
// page was modified, don't steal it
vm_page_set_state(page, PAGE_STATE_MODIFIED);
continue;
} else if ((flags & PAGE_ACCESSED) != 0) {
} else if ((flags & PAGE_ACCESSED) != 0 && !desperate) {
// page is in active use, don't steal it
vm_page_set_state(page, PAGE_STATE_ACTIVE);
continue;