Messages in this thread | | | From | <> | Subject | RE: [PATCH 2/5] vmevent: Convert from deferred timer to deferred work | Date | Fri, 8 Jun 2012 07:05:46 +0000 |
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> -----Original Message----- > From: ext Anton Vorontsov [mailto:anton.vorontsov@linaro.org] > Sent: 08 June, 2012 09:58 ... > If you're saying that we should set up a timer in the userland and constantly > read /proc/vmstat, then we will cause CPU wake up every 100ms, which is > not acceptable. Well, we can try to introduce deferrable timers for the > userspace. But then it would still add a lot more overhead for our task, as this > solution adds other two context switches to read and parse /proc/vmstat. I > guess this is not a show-stopper though, so we can discuss this. > > Leonid, Pekka, what do you think about the idea?
Seems to me not nice solution. Generating/parsing vmstat every 100ms plus wakeups it is what exactly should be avoid to have sense to API. It also will cause page trashing because user-space code could be pushed out from cache if VM decide.
> > Thanks, > > -- > Anton Vorontsov > Email: cbouatmailru@gmail.com
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