-----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