Hello, Li. On Wed, May 20, 2015 at 06:05:37PM +0800, Zefan Li wrote: > > The latency is bound by synchronize_sched_expedited(). Given the way > > cgroups are used in majority of setups (process migration happening > > only during service / session setups), I think this should be okay. > > Actually process migration can happen quite frequently, for example in > Android phones, and that's why Google had an out-of-tree patch to remove > the synchronize_rcu() in that path, which turned out to be buggy. It's still not a very frequent operation tho. We're talking about users switching fore/background jobs here and the expedited synchronization w/ preemption enabled doesn't take much time. In addition, as it currently stands, android is doing memory charge immigration on each fore/background switches. I'm pretty doubtful this would make any difference. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
