Re: [Qemu-devel] Why is SeaBIOS used with -kernel?

[Richard W.M. Jones]

On Fri, Apr 01, 2016 at 06:25:24PM -0400, Kevin O'Connor wrote:
> I'm getting different results.  When you have time we should probably
> track down the discrepancy.  Some of the difference is likely due to
> different hardware (I'm using kvm on an old AMD machine) and some is
> likely due to different test methodology (I'm timing SeaBIOS debug
> output).  However, the changes on that testing branch reliably improve
> the boot by 70ms for me when there is a virtio-scsi device present.

Indeed - I have retested everything in the cold light of day, and
it does save time.

SeaBIOS master branch from current git:

Result: 974.2ms ±2.0ms
Result: 988.5ms ±11.3ms
Result: 974.9ms ±7.3ms

SeaBIOS KevinOConnor/testing branch:

Result: 942.5ms ±4.2ms
Result: 930.0ms ±2.1ms
Result: 934.7ms ±3.4ms

(Note these times are not comparable with the previous ones, because
in a parallel set of investigations I've disabled libvirt and am
running qemu directly, so there is no libvirt overhead.)

Thanks,
Rich.

-- 
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