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

[David Greaves <david@dgreaves.com>]

Michael Tokarev wrote:
> 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.

or netconsole is actually pretty easy and incredibly useful in this kind of
situation even if there's no disk at all :)

David