* Damien Wyart <damien.wyart@xxxxxxx> wrote: > > > Load average is between 0.30 and 0.60 when the machine is idle, the > > > two ksoftirqd threads get a very high total running time in top. > > > This is on a P4 machine. On a recent laptop, the load is not as > > > high, but the ksoftirqd threads also get a very high total running > > > time. > > > Mind having a look at this anomaly with the function graph tracer? We are > > interested in a representative trace that shows the weird ksoftirq activities. > > [ which trace could possibly pinpoint their origin. ] > > > Here's the tracing quickstart: > > > http://redhat.com/~mingo/tip.git/tracing-quickstart.txt > > > Also attached below. Let me know if you have trouble getting a good trace, > > or if any of the steps were non-intuitive or burdensome to you. > > Thanks for your feedback & explanations; I will try to have a look at > all this material asap, I think tomorrow. Note that if the box you test this on is multi-core or HT, then interpreting traces is easier if there's just a single CPU to look at. In that case i'd suggest to reproduce with just a single core, by turning the second one off: echo 0 > /sys/devices/system/cpu/cpu1/online Or, if the problem only occurs with two cpus, restrict tracing to CPU#1: echo 2 > /debug/tracing/tracing_cpumask Ingo -- To unsubscribe from this list: send the line "unsubscribe kernel-testers" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
