Messages in this thread | | | Subject | Re: [PATCH] process cputimer is moving faster than its corresponding clock | From | Olivier Langlois <> | Date | Sun, 14 Apr 2013 21:55:09 -0400 |
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On Fri, 2013-04-12 at 11:16 +0200, Peter Zijlstra wrote: > On Wed, 2013-04-10 at 11:48 -0400, Olivier Langlois wrote: > > Please explain how expensive it is. All I am seeing is a couple of > > additions. > > Let me start with this, since your earlier argument also refers to > this. > > So yes it does look simple and straight fwd, only one addition. However > its an atomic operation across all threads of the same process. Imagine > a single process with 512 threads, all running on a separate cpu. > Peter,
It now makes perfect sense. Thank you for your explanation. It is showing me an aspect that I did overlook.
Greetings,
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