Re: 2.6.23.1: mdadm/raid5 hung/d-state

[Michael Tokarev <mjt@tls.msk.ru>]

Justin Piszcz wrote:
> On Sun, 4 Nov 2007, Michael Tokarev wrote:
[]
>> The next time you come across something like that, do a SysRq-T dump and
>> post that.  It shows a stack trace of all processes - and in particular,
>> where exactly each task is stuck.

> Yes I got it before I rebooted, ran that and then dmesg > file.
> 
> Here it is:
> 
> [1172609.665902]  ffffffff80747dc0 ffffffff80747dc0 ffffffff80747dc0 ffffffff80744d80
> [1172609.668768]  ffffffff80747dc0 ffff81015c3aa918 ffff810091c899b4 ffff810091c899a8

That's only partial list.  All the kernel threads - which are most important
in this context - aren't shown.  You ran out of dmesg buffer, and the most
interesting entries was at the beginning.  If your /var/log partition is
working, the stuff should be in /var/log/kern.log or equivalent.  If it's
not working, there is a way to capture the info still, by stopping syslogd,
cat'ing /proc/kmsg to some tmpfs file and scp'ing it elsewhere.

/mjt