Messages in this thread | | | Date | Thu, 04 Aug 2011 13:46:42 -0500 | From | Anthony Liguori <> | Subject | Re: [RFC PATCH 0/3] Avoid soft lockup message when KVM is stopped by host |
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On 08/04/2011 03:37 AM, Dor Laor wrote: > On 08/03/2011 05:24 PM, Eric B Munson wrote: >> This set is just a rough first pass at avoiding soft lockup warnings >> when a host >> pauses the execution of a guest. A flag is set by the host in the >> shared page >> used for the pvclock when the host goes to stop the guest. When the guest >> resumes and detects a soft lockup, this flag is checked and cleared >> and the soft >> lockup message is skipped. > > While this will cover the case were the host stops a guest, there will > be other plain cases where the host is just over committed and will > cause a softlockup false positive on the guest. > > Softlockup should use stolen time that makes use of the guest running > info would cover both cases
At least in the current steal time implementation, there are numerous cases where steal time is not accounted but you'd hit a soft lockup.
Pausing an idle guest via (qemu) stop is an example. Likewise, a guest that is descheduled while idle but then not scheduled for prolonged periods of time would also not be accounted as steal time.
Regards,
Anthony Liguori
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