Re: [PATCH 0/4] Really lazy fpu

From: H. Peter Anvin
Date: Wed Jun 16 2010 - 03:32:36 EST


On 06/16/2010 12:24 AM, Avi Kivity wrote:
>
> Ingo, Peter, any feedback on this?
>

Conceptually, this makes sense to me. However, I have a concern what
happens when a task is scheduled on another CPU, while its FPU state is
still in registers in the original CPU. That would seem to require
expensive IPIs to spill the state in order for the rescheduling to
proceed, and this could really damage performance.

-hpa

--
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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