Re: [Qemu-devel] Guest bootup time varies with simulated memory size

[Mulyadi Santosa]

Hi Adnan...

On Wed, Feb 9, 2011 at 05:45, Adnan Khaleel <address@hidden> wrote:
> In trying out various simulated memory sized in Qemu, there is a noticeable
> increase in guest bootup times with more memory. My metric of measuring how
> long linux takes to boot is probably not the most consistent but here is
> what I've observed.
> In Qemu 0.12.5
> 512m ~ 4 mins
> 2048m ~ 7 mins
> In the latest version of Qemu 0.14.0-rc0, things have improved
> 512m ~ 3 mins 30 secs
> 2048m ~ 4 mins 45 secs

Interesting number.... things I suggest for further testing:

1. what happen if you also pass "mem=<nn>" to kernel parameter?

2. if the kernel your linux distro use is enabling PAE (hence 64 GiB
support), try to fall back to non PAE one....

3. what happen if you increase the translated code cache size
(-tb-size parameter)?

anyway, it could be something related to a small patch submitted weeks
ago by somebody, which reinsert the last executed TB back to head of
the code list

-- 
regards,

Mulyadi Santosa
Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com
training: mulyaditraining.blogspot.com