Messages in this thread | | | Date | Wed, 21 Aug 2013 18:41:46 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH 2/4] nohz: Synchronize sleep time stats with seqlock |
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On 08/21, Peter Zijlstra wrote: > > The other consideration is that this adds two branches to the normal > schedule path. I really don't know what the regular ratio between > schedule() and io_schedule() is -- and I suspect it can very much depend > on workload -- but it might be a net loss due to that, even if it makes > io_schedule() 'lots' cheaper.
Yes, agreed. Please ignore it for now, I didn't try to actually suggest this change. And even if this is fine perfomance wise, this needs some benchmarking.
Well. actually I have a vague feeling that _perhaps_ this change can help to solve other problems we are discussing, but I am not sure and right now I can't even explain the idea to me.
In short: please ignore ;)
Oleg.
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