Commit graph

6 commits

Author SHA1 Message Date
Ken Chen
480b9434c5 sched: reduce schedstat variable overhead a bit
schedstat is useful in investigating CPU scheduler behavior.  Ideally,
I think it is beneficial to have it on all the time.  However, the
cost of turning it on in production system is quite high, largely due
to number of events it collects and also due to its large memory
footprint.

Most of the fields probably don't need to be full 64-bit on 64-bit
arch.  Rolling over 4 billion events will most like take a long time
and user space tool can be made to accommodate that.  I'm proposing
kernel to cut back most of variable width on 64-bit system.  (note,
the following patch doesn't affect 32-bit system).

Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-10-18 21:32:56 +02:00
Ingo Molnar
2d72376b3a sched: clean up schedstats, cnt -> count
rename all 'cnt' fields and variables to the less yucky 'count' name.

yuckage noticed by Andrew Morton.

no change in code, other than the /proc/sched_debug bkl_count string got
a bit larger:

   text    data     bss     dec     hex filename
  38236    3506      24   41766    a326 sched.o.before
  38240    3506      24   41770    a32a sched.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-15 17:00:12 +02:00
Ingo Molnar
75d4ef16a6 sched: fix delay accounting performance regression
fix delay accounting performance regression - those sched_clock()
calls are not needed.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2007-10-15 17:00:08 +02:00
Ingo Molnar
c3c7011969 [PATCH] sched: add schedstat_set() API
add the schedstat_set() API, to allow the reduction of
CONFIG_SCHEDSTAT related #ifdefs. No code changed.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-08-02 17:41:40 +02:00
Balbir Singh
172ba844a8 sched: update delay-accounting to use CFS's precise stats
update delay-accounting to use CFS's precise stats.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-07-09 18:52:00 +02:00
Ingo Molnar
425e0968a2 sched: move code into kernel/sched_stats.h
create sched_stats.h and move sched.c schedstats code into it.
This cleans up sched.c a bit.

no code changes are caused by this patch.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2007-07-09 18:51:58 +02:00