diff options
| author | Eric Dumazet <eric.dumazet@gmail.com> | 2012-03-23 23:02:53 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-03-24 00:58:42 +0100 |
| commit | 59a32e2ce5eb809967cac4e718bc527beca83c59 (patch) | |
| tree | 3024b71063f497c138680c36c5f7ce2dee563680 /lib/vsprintf.c | |
| parent | fs/proc/kcore.c: make get_sparsemem_vmemmap_info() static (diff) | |
| download | linux-59a32e2ce5eb809967cac4e718bc527beca83c59.tar.xz linux-59a32e2ce5eb809967cac4e718bc527beca83c59.zip | |
proc: speed up /proc/stat handling
On a typical 16 cpus machine, "cat /proc/stat" gives more than 4096 bytes,
and is slow :
# strace -T -o /tmp/STRACE cat /proc/stat | wc -c
5826
# grep "cpu " /tmp/STRACE
read(0, "cpu 1949310 19 2144714 12117253"..., 32768) = 5826 <0.001504>
Thats partly because show_stat() must be called twice since initial
buffer size is too small (4096 bytes for less than 32 possible cpus)
Fix this by :
1) Taking into account nr_irqs in the initial buffer sizing.
2) Using ksize() to allow better filling of initial buffer.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Glauber Costa <glommer@parallels.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib/vsprintf.c')
0 files changed, 0 insertions, 0 deletions