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| author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-11-13 01:14:44 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-11-13 01:14:44 +0300 |
| commit | 44048d700bcbfaf4bcca6e2e0a73d89d01ec0878 (patch) | |
| tree | 975427ee367023b6e3a254519d5e5fdced2c0969 | |
| parent | e6a5c27f3b0fef72e528fc35e343af4b2db790ff (diff) | |
| download | linux-44048d700bcbfaf4bcca6e2e0a73d89d01ec0878.tar.xz | |
Revert "Bias the placement of kernel pages at lower PFNs"
This reverts commit 5adc5be7cd1bcef6bb64f5255d2a33f20a3cf5be.
Alexey Dobriyan reports that it causes huge slowdowns under some loads,
in his case a "mkfs.ext2" on a 30G partition. With the placement bias,
the mkfs took over four minutes, with it reverted it's back to about ten
seconds for Alexey.
Reported-and-tested-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/page_alloc.c | 20 |
1 files changed, 0 insertions, 20 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index da69d833e067..12376ae3f733 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -749,23 +749,6 @@ int move_freepages_block(struct zone *zone, struct page *page, int migratetype) return move_freepages(zone, start_page, end_page, migratetype); } -/* Return the page with the lowest PFN in the list */ -static struct page *min_page(struct list_head *list) -{ - unsigned long min_pfn = -1UL; - struct page *min_page = NULL, *page;; - - list_for_each_entry(page, list, lru) { - unsigned long pfn = page_to_pfn(page); - if (pfn < min_pfn) { - min_pfn = pfn; - min_page = page; - } - } - - return min_page; -} - /* Remove an element from the buddy allocator from the fallback list */ static struct page *__rmqueue_fallback(struct zone *zone, int order, int start_migratetype) @@ -789,11 +772,8 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order, if (list_empty(&area->free_list[migratetype])) continue; - /* Bias kernel allocations towards low pfns */ page = list_entry(area->free_list[migratetype].next, struct page, lru); - if (unlikely(start_migratetype != MIGRATE_MOVABLE)) - page = min_page(&area->free_list[migratetype]); area->nr_free--; /* |