[Ocfs2-users] Slow umounts on SLES10 patchlevel 3 ocfs2

[Sunil Mushran]

It was designed to run in prod envs.

On 07/07/2011 12:21 AM, Marc Grimme wrote:
> Sunil,
> can I query those figures during runtime of a productive cluster?
> Or might it influence the availability performance what ever?
>
> Thanks for your help.
> Marc.
> ----- "Sunil Mushran"<sunil.mushran at oracle.com>  wrote:
>
>> umount is a two step process. First the fs frees the inodes. Then the
>> o2dlm takes stock of all active resources and migrates ones that are
>> still in use. This typically takes some time. But I have never heard
>> of it taking 45 mins.
>>
>> But I guess it could be if one has a lot of resources. Lets start by
>> getting a count.
>>
>> This will dump the number of cluster locks held by the fs.
>> # for vol in /sys/kernel/debug/ocfs2/*
>>       do
>>           count=$(wc -l ${vol}/locking_state | cut -f1 -d' ');
>>           echo "$(basename ${vol}): ${count} locks" ;
>>       done;
>>
>> This will dump the number of lock resources known to the dlm.
>> # for vol in /sys/kernel/debug/o2dlm/*
>>       do
>>           count=$(grep -c "^NAME:" ${vol}/locking_state);
>>           echo "$(basename ${vol}): ${count} resources" ;
>>       done;
>>
>> The debugfs needs to be mounted for this to work.
>> mount -t debugfs none /sys/kernel/debug
>>
>> Sunil
>>
>> On 07/06/2011 08:20 AM, Marc Grimme wrote:
>>> Hi,
>>> we are using a SLES10 Patchlevel 3 with 12 Nodes hosting tomcat
>> application servers.
>>> The cluster was running some time (about 200 days) without
>> problems.
>>> Recently we needed to shutdown the cluster for maintenance and
>> experianced very long times for the umount of the filesystem. It took
>> something like 45 minutes each node and filesystem (12 x 45 minutes
>> shutdown time).
>>> As a result the planned downtime had to be extended ;-) .
>>>
>>> Is there any tuning option or the like to make those umounts faster
>> or is this something we have to live with?
>>> Thanks for your help.
>>> If you need more information let me know.
>>>
>>> Marc.
>>>
>>> Some info on the configuration:
>>> ---------------------------X8-----------------------------------
>>> # /sbin/modinfo ocfs2
>>> filename:
>> /lib/modules/2.6.16.60-0.54.5-smp/kernel/fs/ocfs2/ocfs2.ko
>>> license:        GPL
>>> author:         Oracle
>>> version:        1.4.1-1-SLES
>>> description:    OCFS2 1.4.1-1-SLES Wed Jul 23 18:33:42 UTC 2008
>> (build f922955d99ef972235bd0c1fc236c5ddbb368611)
>>> srcversion:     986DD1EE4F5ABD8A44FF925
>>> depends:        ocfs2_dlm,jbd,ocfs2_nodemanager
>>> supported:      yes
>>> vermagic:       2.6.16.60-0.54.5-smp SMP gcc-4.1
>>> atix at CAS12:~>   /sbin/modinfo ocfs2_dlm
>>> filename:
>> /lib/modules/2.6.16.60-0.54.5-smp/kernel/fs/ocfs2/dlm/ocfs2_dlm.ko
>>> license:        GPL
>>> author:         Oracle
>>> version:        1.4.1-1-SLES
>>> description:    OCFS2 DLM 1.4.1-1-SLES Wed Jul 23 18:33:42 UTC 2008
>> (build f922955d99ef972235bd0c1fc236c5ddbb368611)
>>> srcversion:     16FE87920EA41CA613E6609
>>> depends:        ocfs2_nodemanager
>>> supported:      yes
>>> vermagic:       2.6.16.60-0.54.5-smp SMP gcc-4.1
>>> parm:           dlm_purge_interval_ms:int
>>> parm:           dlm_purge_locks_max:int
>>> # rpm -qa ocfs2*
>>> ocfs2-tools-1.4.0-0.9.9
>>> ocfs2console-1.4.0-0.9.9
>>> ---------------------------X8-----------------------------------
>>> The kernel version is 2.6.16.60-0.54.5-smp
>>>
>>>
>> ______________________________________________________________________________
>>> Marc Grimme
>>>
>>> E-Mail: grimme at atix.de