diff options
Diffstat (limited to '0017-ZEN-mm-Lower-the-non-hugetlbpage-pageblock-size-to-r.patch')
| -rw-r--r-- | 0017-ZEN-mm-Lower-the-non-hugetlbpage-pageblock-size-to-r.patch | 45 |
1 files changed, 0 insertions, 45 deletions
diff --git a/0017-ZEN-mm-Lower-the-non-hugetlbpage-pageblock-size-to-r.patch b/0017-ZEN-mm-Lower-the-non-hugetlbpage-pageblock-size-to-r.patch deleted file mode 100644 index 11b98001f453..000000000000 --- a/0017-ZEN-mm-Lower-the-non-hugetlbpage-pageblock-size-to-r.patch +++ /dev/null @@ -1,45 +0,0 @@ -From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 -From: Sultan Alsawaf <sultan@kerneltoast.com> -Date: Wed, 20 Oct 2021 20:50:11 -0700 -Subject: [PATCH] ZEN: mm: Lower the non-hugetlbpage pageblock size to reduce - scheduling delays - -The page allocator processes free pages in groups of pageblocks, where -the size of a pageblock is typically quite large (1024 pages without -hugetlbpage support). Pageblocks are processed atomically with the zone -lock held, which can cause severe scheduling delays on both the CPU -going through the pageblock and any other CPUs waiting to acquire the -zone lock. A frequent offender is move_freepages_block(), which is used -by rmqueue() for page allocation. - -As it turns out, there's no requirement for pageblocks to be so large, -so the pageblock order can simply be reduced to ease the scheduling -delays and zone lock contention. PAGE_ALLOC_COSTLY_ORDER is used as a -reasonable setting to ensure non-costly page allocation requests can -still be serviced without always needing to free up more than one -pageblock's worth of pages at a time. - -This has a noticeable effect on overall system latency when memory -pressure is elevated. The various mm functions which operate on -pageblocks no longer appear in the preemptoff tracer, where previously -they would spend up to 100 ms on a mobile arm64 CPU processing a -pageblock with preemption disabled and the zone lock held. - -Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com> ---- - include/linux/pageblock-flags.h | 2 +- - 1 file changed, 1 insertion(+), 1 deletion(-) - -diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h -index 83c7248053a1eb745e0bff410be66d0f04a5e8bb..d2b8741eabf7e01802dbb0705a12cb2e5c80ea1d 100644 ---- a/include/linux/pageblock-flags.h -+++ b/include/linux/pageblock-flags.h -@@ -48,7 +48,7 @@ extern unsigned int pageblock_order; - #else /* CONFIG_HUGETLB_PAGE */ - - /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */ --#define pageblock_order (MAX_ORDER-1) -+#define pageblock_order PAGE_ALLOC_COSTLY_ORDER - - #endif /* CONFIG_HUGETLB_PAGE */ - |