On 06/23/2014 09:55 AM, Dave Hansen wrote: > This still has a regression. Commit 1ed70de (from Paul's git tree), > gets a result of 52231880. If I back up two commits to v3.16-rc1 and > revert ac1bea85 (the original culprit) the result goes back up to 57308512. > > So something is still going on here. > > I'll go back and compare the grace period ages to see if I can tell what > is going on.
RCU_TRACE interferes with the benchmark a little bit, and it lowers the delta that the regression causes. So, evaluate this cautiously. According to rcu_sched/rcugp, the average "age" is: v3.16-rc1, with ac1bea85 reverted: 10.7 v3.16-rc1, plus e552592e: 6.1 Paul, have you been keeping an eye on rcugp? Even if I run my system with only 10 threads, I still see this basic pattern where the average "age" is lower when I see lower performance. It seems to be a reasonable proxy that could be used instead of waiting on me to re-run tests. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
