Re: regression: 100% io-wait with 2.6.24-rcX

Ingo Molnar
2008-01-07T11:19:48Z

* Joerg Platte <lists@naasa.net> wrote:

> Hi,
>
> when booting kernel 2.6.24-rc{4,5,6,7} top reports up to 100% iowait,
> even if no program accesses the disc on my Thinkpad T40p. Kernel
> 2.6.23.12 does not suffer from this. Is there anything I can do to
> find out which process or which part of the kernel is responsible for
> this? I can try to bisect it, but maybe there are other possibilities
> to debug this, since I cannot boot this computer frequently. I
> discovered, that there is no iowait within the first few seconds after
> waking up from suspend to ram...

do:

echo t > /proc/sysrq-trigger

and send us the dmesg output. If the dmesg output does not include the
bootup bits then increase CONFIG_LOG_BUF_SHIFT to 20 or so:

CONFIG_LOG_BUF_SHIFT=20

to have a large enough kernel messages buffer.

Ingo