Re: [Qemu-devel] Anyone seeing huge slowdown launching qemu with Linux 2.6.35?

[Richard W.M. Jones]

On Tue, Aug 03, 2010 at 07:10:18PM +0300, Avi Kivity wrote:
> -kernel and -initrd is a developer's interface intended to make life
> easier for users that use qemu to develop kernels.  It was not
> intended as a high performance DMA engine.  Neither was the firmware
> _configuration_ interface.  That is what virtio and to a lesser
> extent IDE was written to perform.  You'll get much better results
> from them.

Firmware configuration replaced something which was already working
really fast -- preloading the images into memory -- with something
which worked slower, and has just recently got _way_ more slow.

This is a regression.  Plain and simple.

I have posted a small patch which makes this 650x faster without
appreciable complication.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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