On Fri, Sep 23, 2016 at 08:42:51AM -0400, Mike Snitzer wrote: > On Fri, Sep 23 2016 at 8:26am -0400, > Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > > On Fri, Sep 23, 2016 at 02:17:10PM +0200, Mike Galbraith wrote: > > > On Fri, 2016-09-23 at 10:00 +0200, Thomas Gleixner wrote: > > > > On Fri, 23 Sep 2016, Peter Zijlstra wrote: > > > > > > > > Is anybody still using PREEMPT_NONE? Most workloads also care about > > > > > latency to some extend. Lots of code has explicit cond_resched() and > > > > > doesn't worry. > > > > > > > > Dunno. But I bet there are workloads which love it. > > > > > > SUSE definitely uses it. I had presumed that was enterprise standard. > > > > Hmm, I thought most distros defaulted to PREEMPT_VOLUNTARY. > > So what is the concensus on this? Switch dm-bufio's cond_resched calls > (in peter's patch) to might_sleep()? Or continue using cond_resched but > fix cond_resched to do the might_sleep() equivalent if PREEMPT_NONE? I'd go with the one I posted and look again if ever a performance issue shows up. -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
