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

[Richard W.M. Jones]

On Wed, Aug 04, 2010 at 02:06:58PM -0600, David S. Ahern wrote:
> 
> 
> On 08/04/10 11:34, Avi Kivity wrote:
> 
> >> And it's awesome for fast prototyping. Of course, once that fast
> >> becomes dog slow, it's not useful anymore.
> > 
> > For the Nth time, it's only slow with 100MB initrds.
> 
> 100MB is really not that large for an initrd.

<note>

I'd just like to note that the libguestfs initrd is uncompressed.

The reason for this is I found that the decompression code in Linux is
really slow.  I have to admit I didn't look into why this is.  By not
compressing it on the host and decompressing it on the guest, we saved
a bunch of boot time (3-5 seconds IIRC).

Anyway, comparing 115MB libguestfs initrd and other initrd sizes may
not be a fair comparison, since almost every other initrd you will see
will be compressed.

</note>

Rich.

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