Messages in this thread | | | From | Rusty Russell <> | Subject | Re: [PATCH] stopmachine: add stopmachine_timeout | Date | Mon, 14 Jul 2008 22:34:40 +1000 |
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On Monday 14 July 2008 21:51:25 Christian Borntraeger wrote: > Am Montag, 14. Juli 2008 schrieb Hidetoshi Seto: > > + /* Wait all others come to life */ > > + while (cpus_weight(prepared_cpus) != num_online_cpus() - 1) { > > + if (time_is_before_jiffies(limit)) > > + goto timeout; > > + cpu_relax(); > > + } > > + > > Hmm. I think this could become interesting on virtual machines. The > hypervisor might be to busy to schedule a specific cpu at certain load > scenarios. This would cause a failure even if the cpu is not really locked > up. We had similar problems with the soft lockup daemon on s390.
5 seconds is a fairly long time. If all else fails we could have a config option to simply disable this code.
> It would be good to not-use wall-clock time, but really used cpu time > instead. Unfortunately I have no idea, if that is possible in a generic > way. Heiko, any ideas?
Ah, cpu time comes up again. Perhaps we should actually dig that up again; Zach and Jeremy CC'd.
Thanks, Rusty.
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