linux/Documentation/vm
Vladimir Davydov f074a8f49e proc: export idle flag via kpageflags
As noted by Minchan, a benefit of reading idle flag from /proc/kpageflags
is that one can easily filter dirty and/or unevictable pages while
estimating the size of unused memory.

Note that idle flag read from /proc/kpageflags may be stale in case the
page was accessed via a PTE, because it would be too costly to iterate
over all page mappings on each /proc/kpageflags read to provide an
up-to-date value.  To make sure the flag is up-to-date one has to read
/sys/kernel/mm/page_idle/bitmap first.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Reviewed-by: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Greg Thelen <gthelen@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-10 13:29:01 -07:00
..
.gitignore
00-INDEX mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
active_mm.txt
balance
cleancache.txt
frontswap.txt
highmem.txt
hugetlbpage.txt Documentation: update libhugetlbfs location and use for testing 2015-09-08 15:35:28 -07:00
hwpoison.txt
idle_page_tracking.txt mm: introduce idle page tracking 2015-09-10 13:29:01 -07:00
ksm.txt
numa
numa_memory_policy.txt
overcommit-accounting
page_migration
page_owner.txt
pagemap.txt proc: export idle flag via kpageflags 2015-09-10 13:29:01 -07:00
remap_file_pages.txt
slub.txt
soft-dirty.txt
split_page_table_lock
transhuge.txt
unevictable-lru.txt
userfaultfd.txt userfaultfd: change the read API to return a uffd_msg 2015-09-04 16:54:41 -07:00
zsmalloc.txt
zswap.txt zswap: update docs for runtime-changeable attributes 2015-09-10 13:29:01 -07:00