[Linux-cluster] GFS Performance Problems (RHEL5)
Paul Risenhoover
prisenhoover at sampledigital.com
Tue Nov 27 23:30:08 UTC 2007
Sorry about this mis-send.
I'm guessing my problem has to do with this:
https://www.redhat.com/archives/linux-cluster/2007-October/msg00332.html
BTW: My file system is 13TB.
I found this article that talks about tuning the glock_purge setting:
http://people.redhat.com/wcheng/Patches/GFS/readme.gfs_glock_trimming.R4
But it seems to require a special kernel module that I don't have :(.
Anybody know where I can get it?
Paul
Paul Risenhoover wrote:
> Hi All,
>
> I am experiencing some substantial performance problems on my RHEL 5
> server running GFS. The specific symptom that I'm seeing is that the
> file system will hang for anywhere from 5 to 45 seconds on occasion.
> When this happens it stalls all processes that are attempting to
> access the file system (ie, "ls -l") such that even a ctrl-break can't
> stop it.
>
> It also appears that gfs_scand is working extremely hard. It runs at
> 7-10% CPU almost constantly. I did some research on this and
> discovered a discussion about cluster locking in relation to
> directories with large numbers of files, and believe it might be
> related. I've got some directories with 5000+ files. However, I get
> the stalling behavior even when nothing is accessing those particular
> directories.
>
> I also tried some tuning some of the parameters:
>
> gfs_tool settune /mnt/promise demote_secs 10
> gfs_tool settune /mnt/promise scand_secs 2
> gfs_tool settune /mnt/promise/ reclaim_limit 1000
>
> But this doesn't appear to have done much. Does anybody have some
> thoughts on how I might resolve this?
>
> Paul
>
> --
> Linux-cluster mailing list
> Linux-cluster at redhat.com
> https://www.redhat.com/mailman/listinfo/linux-cluster
More information about the Linux-cluster
mailing list