Re: High vm-exit latencies during kvm boot-up/shutdown

Jan Kiszka
2007-10-23T14:44:57Z

Jan Kiszka wrote:
> Avi Kivity wrote:
>> Seeing vmx_vcpu_run() in there confuses me, as it always runs with
>> interrupts disabled (it does dispatch NMIs, so we could be seeing an NMI).
>
> The point is that the cyclictest does not find large latencies when kvm
> is not happening to start or stop right now. And if you are thinking
> about NMIs triggered by the kvm code on vm-exit: I also instrumented
> that code path, and it is not taken in case of the long delay.

Actually, that instrumentation was for an older version. In this one
here, the vm-entry/exit block is clearly framed by traced vmcs_xxx calls.

Jan

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