Re: Which kernel options should be enabled to find the root cause of this bug?

[Justin Piszcz <jpiszcz@lucidpixels.com>]

On Tue, 24 Nov 2009, Eric Sandeen wrote:

> Justin Piszcz wrote:
>>
>>
>> On Sat, 17 Oct 2009, Justin Piszcz wrote:
>>
>>> Hello,
>>>
>>> I have a system I recently upgraded from 2.6.30.x and after
>>> approximately 24-48 hours--sometimes longer, the system cannot write
>>> any more files to disk (luckily though I can still write to /dev/shm)
>>> -- to which I have
>>> saved the sysrq-t and sysrq-w output:
>>>
>>> http://home.comcast.net/~jpiszcz/20091017/sysrq-w.txt
>>> http://home.comcast.net/~jpiszcz/20091017/sysrq-t.txt
>
> Unfortunately it looks like a lot of the sysrq-t, at least, was lost.
Yes, when this occurred the first few times, I can only grab whats in dmesg
to the ramdisk, trying to access any file system other than the ramdisk
(tmpfs) /dev/shm, will cause the process to be locked.

>
> The sysrq-w trace has the "show blocked state" start a ways down the file,
> for anyone playing along at home ;)
>
> Other things you might try are a sysrq-m to get memory state...
I actually performed most of the useful sysrq-commands, please see
the following:

wget http://home.comcast.net/~jpiszcz/20091018/dmesg.txt
wget http://home.comcast.net/~jpiszcz/20091018/interrupts.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-l.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-m.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-p.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-q.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-t.txt
wget http://home.comcast.net/~jpiszcz/20091018/sysrq-w.txt

>
>>> Configuration:
>>>
>>> $ cat /proc/mdstat Personalities : [raid1] [raid6] [raid5] [raid4] md1
>>> : active raid1 sdb2[1] sda2[0]
>>>      136448 blocks [2/2] [UU]
>>>
>>> md2 : active raid1 sdb3[1] sda3[0]
>>>      129596288 blocks [2/2] [UU]
>>>
>>> md3 : active raid5 sdj1[7] sdi1[6] sdh1[5] sdf1[3] sdg1[4] sde1[2]
>>> sdd1[1] sdc1[0]
>>>      5128001536 blocks level 5, 1024k chunk, algorithm 2 [8/8] [UUUUUUUU]
>>>
>>> md0 : active raid1 sdb1[1] sda1[0]
>>>      16787776 blocks [2/2] [UU]
>>>
>>> $ mount
>>> /dev/md2 on / type xfs (rw,noatime,nobarrier,logbufs=8,logbsize=262144)
>>> tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
>>> proc on /proc type proc (rw,noexec,nosuid,nodev)
>>> sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
>>> udev on /dev type tmpfs (rw,mode=0755)
>>> tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
>>> devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)
>>> /dev/md1 on /boot type ext3 (rw,noatime)
>>> /dev/md3 on /r/1 type xfs
>>> (rw,noatime,nobarrier,logbufs=8,logbsize=262144)
>>> rpc_pipefs on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
>>> nfsd on /proc/fs/nfsd type nfsd (rw)
>
> Do you get the same behavior if you don't add the log options at mount time?
I have not tried disabling the log options, although they have been in effect
for a long time, (the logsbufs and bufsize and recently) the nobarrier
support.  Could there be an issue using -o nobarrier on a raid1+xfs?