2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-24 05:04:00 +08:00
linux-next/mm
Christoph Lameter 9614634fe6 [PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O
It turns out that it is advantageous to leave a small portion of unmapped file
backed pages if all of a zone's pages (or almost all pages) are allocated and
so the page allocator has to go off-node.

This allows recently used file I/O buffers to stay on the node and
reduces the times that zone reclaim is invoked if file I/O occurs
when we run out of memory in a zone.

The problem is that zone reclaim runs too frequently when the page cache is
used for file I/O (read write and therefore unmapped pages!) alone and we have
almost all pages of the zone allocated.  Zone reclaim may remove 32 unmapped
pages.  File I/O will use these pages for the next read/write requests and the
unmapped pages increase.  After the zone has filled up again zone reclaim will
remove it again after only 32 pages.  This cycle is too inefficient and there
are potentially too many zone reclaim cycles.

With the 1% boundary we may still remove all unmapped pages for file I/O in
zone reclaim pass.  However.  it will take a large number of read and writes
to get back to 1% again where we trigger zone reclaim again.

The zone reclaim 2.6.16/17 does not show this behavior because we have a 30
second timeout.

[akpm@osdl.org: rename the /proc file and the variable]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:26:59 -07:00
..
bootmem.c [PATCH] x86_64: Handle empty PXMs that only contain hotplug memory 2006-04-09 11:53:16 -07:00
fadvise.c [PATCH] sys_sync_file_range() 2006-03-31 12:18:54 -08:00
filemap_xip.c [PATCH] mark address_space_operations const 2006-06-28 14:59:04 -07:00
filemap.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-06-30 15:39:30 -07:00
filemap.h [PATCH] generic_file_buffered_write(): handle zero-length iovec segments 2006-06-29 10:26:20 -07:00
fremap.c [PATCH] fix update_mmu_cache in fremap.c 2006-06-23 07:42:52 -07:00
highmem.c [PATCH] zoned vm counters: conversion of nr_bounce to per zone counter 2006-06-30 11:25:36 -07:00
hugetlb.c [PATCH] tightening hugetlb strict accounting 2006-06-23 07:42:48 -07:00
internal.h [PATCH] remove set_page_count() outside mm/ 2006-03-22 07:54:02 -08:00
Kconfig Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/pci-2.6 2006-06-29 10:49:17 -07:00
madvise.c [PATCH] Fix MADV_REMOVE protection checking 2006-04-17 18:22:18 -07:00
Makefile [PATCH] zoned vm counters: create vmstat.c/.h from page_alloc.c/.h 2006-06-30 11:25:34 -07:00
memory_hotplug.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
memory.c [PATCH] Light weight event counters 2006-06-30 11:25:36 -07:00
mempolicy.c [PATCH] Use Zoned VM Counters for NUMA statistics 2006-06-30 11:25:36 -07:00
mempool.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-03-26 09:41:18 -08:00
migrate.c [PATCH] Allow migration of mlocked pages 2006-06-25 10:00:55 -07:00
mincore.c [PATCH] freepgt: sys_mincore ignore FIRST_USER_PGD_NR 2005-04-19 13:29:20 -07:00
mlock.c [PATCH] move capable() to capability.h 2006-01-11 18:42:13 -08:00
mmap.c [PATCH] zoned vm counters: conversion of nr_pagecache to per zone counter 2006-06-30 11:25:34 -07:00
mmzone.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
mprotect.c [PATCH] add page_mkwrite() vm_operations method 2006-06-23 07:42:51 -07:00
mremap.c [PATCH] move capable() to capability.h 2006-01-11 18:42:13 -08:00
msync.c [PATCH] Kill PF_SYNCWRITE flag 2006-06-23 17:10:39 +02:00
nommu.c [PATCH] zoned vm counters: conversion of nr_pagecache to per zone counter 2006-06-30 11:25:34 -07:00
oom_kill.c [PATCH] mm: fix typos in comments in mm/oom_kill.c 2006-06-23 07:42:47 -07:00
page_alloc.c [PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O 2006-07-03 15:26:59 -07:00
page_io.c [PATCH] Light weight event counters 2006-06-30 11:25:36 -07:00
page-writeback.c [PATCH] zoned vm counters: remove useless struct wbs 2006-06-30 11:25:36 -07:00
pdflush.c [PATCH] pdflush: handle resume wakeups 2006-06-25 10:01:06 -07:00
prio_tree.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
readahead.c spelling fixes 2006-06-26 18:35:02 +02:00
rmap.c [PATCH] zoned vm counters: split NR_ANON_PAGES off from NR_FILE_MAPPED 2006-06-30 11:25:35 -07:00
shmem.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bunk/trivial 2006-06-30 15:39:30 -07:00
slab.c [PATCH] slab: consolidate code to free slabs from freelist 2006-06-30 11:25:36 -07:00
slob.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
sparse.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
swap_state.c [PATCH] zoned vm counters: conversion of nr_pagecache to per zone counter 2006-06-30 11:25:34 -07:00
swap.c [PATCH] Light weight event counters 2006-06-30 11:25:36 -07:00
swapfile.c Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
thrash.c [PATCH] temporarily disable swap token on memory pressure 2005-11-28 14:42:25 -08:00
tiny-shmem.c [PATCH] devfs: Remove the devfs_fs_kernel.h file from the tree 2006-06-26 12:25:08 -07:00
truncate.c [PATCH] Remove semi-softlockup from invalidate_mapping_pages 2006-06-23 07:43:07 -07:00
util.c [PATCH] slab: optimize constant-size kzalloc calls 2006-03-25 08:22:49 -08:00
vmalloc.c [PATCH] mm: introduce remap_vmalloc_range() 2006-06-23 07:42:49 -07:00
vmscan.c [PATCH] ZVC/zone_reclaim: Leave 1% of unmapped pagecache pages for file I/O 2006-07-03 15:26:59 -07:00
vmstat.c [PATCH] Light weight event counters 2006-06-30 11:25:36 -07:00