Re: [Qemu-devel] Boot Problems Windows XP guest

[Benoît Canet]

> thanks for your help. I cloned the git and compiled it - but I'm not
> completely sure how to enable the throttling finally - there were
> several mails regarding averages and max values... And the "unit" of
> the values would be interesting.

Hi Erik,

The main settings are bps, bps_rd and bps_wr for total, read and write bandwith
throttling (unit is bytes) and iops, iops_rd, iops_wr for IO per second
throttling (unit is IO operation).

You should specify your settings on the -drive command line like in:
-drive file=foo.raw,if=virtio,cache=none,bps=1048576 for a 1 MB total bandwith.

In addition to that there is another set of parameters to configure the burst
ability of the throttling.
These setting are: bps_max, bps_rd_max, bps_wr_max, iops_mx, iops_rd_max, and
iops_wr_max.

Some bursting is enabled by default.

>From what Paolo said you should set bps_max = 1 to specify that the default
bursting is not set.

So:
-drive file=foo.raw,if=virtio,cache=none,bps=1048576,bps_max=1 for a 1 MB total
bandwith with almost no burst.

Best regards

Benoît

ps: take care of updating your repository and recompiling it since I made some
changes for you to use. (use git fetch origin)

> 
> Merci beaucoup.
> 
> Best regards,
> 
> Erik
> 
> 
>