Messages in this thread | | | Date | Fri, 24 Jul 2009 15:16:49 +0200 | From | Andi Kleen <> | Subject | Re: [PATCH] x86: Use clflush() instead of wbinvd() whenever possible when changing mapping |
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> No. It was motivated by the assumption that wbinvd() is just bad:
Ok, got it now.
> Qoute: > > WBINVD is a very nasty operation. I was talking to some CPU people and they > really recommended to get rid of it as far as possible. Stopping the CPU > for msecs is just wrong and there are apparently even some theoretical live > lock situations. - It is not interruptible in earlier VT versions and > messes up real time in the hypervisor. Some people were doing KVM on rt > kernels and had latency spikes from that. > > > /Qoute > (I believe you wrote that ?)
Yes. That's still true and that's one reason to not use it.
-Andi
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