Re: [PATCH] Lazy FPU for SVM

Avi Kivity
2007-04-24T10:39:14Z

Anthony Liguori wrote:

[updated patch]

Applied.

>
> Hard to say exactly because of the noise. I did two runs of 4
> test/vmexit:
>
> Before 4091, 4194, 4559, 4439
> After: 3979, 4324, 3918, 3910
>
> So there's definitely a speedup, but probably only 100-200 cycles.
>

Running on an idle, headless server with the vcpu pinned reduces
variability to a few cycles in the after case. Strangely, the
variability is high in the before case. I get a similar disappointing
result of 100-200 cycles.

--
Do not meddle in the internals of kernels, for they are subtle and quick to panic.