Messages in this thread | | | Subject | Re: [PATCH] watchdog: Make sure the watchdog thread gets CPU on loaded system | From | Peter Zijlstra <> | Date | Thu, 15 Mar 2012 17:16:43 +0100 |
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On Thu, 2012-03-15 at 17:11 +0100, Peter Zijlstra wrote: > On Thu, 2012-03-15 at 17:10 +0100, Peter Zijlstra wrote: > > On Thu, 2012-03-15 at 08:39 -0700, Mandeep Singh Baines wrote: > > > Its a good tool for catching problems of scale. As we move to more and > > > more cores you'll uncover bugs where data structures start to blow up. > > > Hash tables get huge, when you have 100000s of processes or millions > > > of > > > TCP flows, or cgroups or namespace. That critical section (spinlock, > > > spinlock_bh, or preempt_disable) that used to be OK might no longer > > > be. > > > > Or you run with the preempt latency tracer. > > Or for that matter run cyclictest...
Thing is, if you want a latency detector, call it that and stop pretending its a useful debug feature. Also, if you want that, set the interval in the 0.1-0.5 seconds range and dump stack on every new max.
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