Messages in this thread | | | Date | Thu, 11 Aug 2011 15:02:32 -0700 | Subject | Re: [PATCH v6 2/2] Output stall data in debugfs | From | Alex Neronskiy <> |
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On Thu, Aug 11, 2011 at 2:17 PM, Peter Zijlstra <peterz@infradead.org> wrote: > On Thu, 2011-08-11 at 13:31 -0700, Alex Neronskiy wrote: >> >> > I mean, we're at the point where a PREEMPT=y kernel has a pretty decent >> > latency and the PREEMPT_RT kernels live at ~30us. So wth are you >> > measuring? >> Well, not all kernels have PREEMPT. Chromebook kernels don't, for example. > > Can one infer from that statement that the purpose is trying to measure > non preempt latency? Why not use the tracer build for that purpose? > > Still the watchdog ticks at 1s intervals or so, anything that takes that > long, even on voluntary preemption kernels is quite insane. I think Don grasped the sentiment well about a month ago when he commented on the first version of the patch, so I'll just resend his words: On Wed, Jul 13, 2011 at 6:43 AM, Don Zickus <dzickus@redhat.com> wrote: > I like the idea of this patch. It definitely helps with better statistics > when trying to set the appropriate values for a soft/hard lockup as > opposed to pulling numbers from the air. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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