diff options
| author | Andrew Shewmaker <agshew@gmail.com> | 2013-04-29 15:08:11 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-04-29 15:54:36 -0700 |
| commit | 4eeab4f5580d11bffedc697684b91b0bca0d5009 (patch) | |
| tree | 4e9a0c010d34e786df52225039a17aa38e9adf17 /kernel/sysctl.c | |
| parent | c9b1d0981fcce3d9976d7b7a56e4e0503bc610dd (diff) | |
mm: replace hardcoded 3% with admin_reserve_pages knob
Add an admin_reserve_kbytes knob to allow admins to change the hardcoded
memory reserve to something other than 3%, which may be multiple
gigabytes on large memory systems. Only about 8MB is necessary to
enable recovery in the default mode, and only a few hundred MB are
required even when overcommit is disabled.
This affects OVERCOMMIT_GUESS and OVERCOMMIT_NEVER.
admin_reserve_kbytes is initialized to min(3% free pages, 8MB)
I arrived at 8MB by summing the RSS of sshd or login, bash, and top.
Please see first patch in this series for full background, motivation,
testing, and full changelog.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: make init_admin_reserve() static]
Signed-off-by: Andrew Shewmaker <agshew@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/sysctl.c')
| -rw-r--r-- | kernel/sysctl.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 6daabb72bdb..9edcf456e0f 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1436,6 +1436,13 @@ static struct ctl_table vm_table[] = { .mode = 0644, .proc_handler = proc_doulongvec_minmax, }, + { + .procname = "admin_reserve_kbytes", + .data = &sysctl_admin_reserve_kbytes, + .maxlen = sizeof(sysctl_admin_reserve_kbytes), + .mode = 0644, + .proc_handler = proc_doulongvec_minmax, + }, { } }; |