Messages in this thread | | | Subject | Re: [PATCH][RFC] Adding information of counts processes acquired how many spinlocks to schedstat | From | Andi Kleen <> | Date | Wed, 01 Jul 2009 09:38:04 +0200 |
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Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> writes:
> Hi, > > I wrote a test patch which add information of counts processes acquired how many spinlocks to schedstat. > After applied this patch, /proc/<PID>/sched will change like this,
The problem is that spinlocks are very common and schedstats is enabled commonly in production kernels. You would need to demonstrate that such a change doesn't have significant performance impact. For me it looks like it has.
Also I'm not sure exactly what good such a metric is. Do you have a concrete use case?
The normal way to check for lock contention or lock bouncingis to simply profile cycles or time and see if there is a lot of CPU time in locks.
-Andi
-- ak@linux.intel.com -- Speaking for myself only.
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