Ocfs2 users - May 2014 - OCFS2 slow when using 'find' and 'du' commands

we've noticed that once we have grown to have thousands (21,839) of
sub-directories running linux commands such as 'find' and 'du'
are very
slow. we compared them by running them directly on a hard-disk with the
same file and directory contents

find ./directory/* -type f -mmin -60

(21,839 directories)
ocfs2 = 10 minutes
direct  = 30 seconds

Are there any tweaks we need to make to help improve performance of these
commands when many sub-directories exist?

ocfs2 nodes = 3

debugfs.ocfs2 1.6.3
        Feature Compat: 3 backup-super strict-journal-super
        Feature Incompat: 9808 sparse inline-data xattr indexed-dirs
discontig-bg
        Feature RO compat: 1 unwritten
        Dynamic Features: (0x0)
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://oss.oracle.com/pipermail/ocfs2-users/attachments/20140522/771cf266/attachment.html

Is this slow the second time you run the command or only the first? How
much memory do you have?

-mmin needs the inode. And reading inodes from disk is expensive. One
reason could be that the system does not have enough memory to cache the
inodes and thus is triggering lots of disk reads.


On Thu, May 22, 2014 at 4:23 PM, Robert Abbate <doctorabbate at
gmail.com>wrote:
> we've noticed that once we have grown to have thousands (21,839) of
> sub-directories running linux commands such as 'find' and
'du' are very
> slow. we compared them by running them directly on a hard-disk with the
> same file and directory contents
>
> find ./directory/* -type f -mmin -60
>
> (21,839 directories)
> ocfs2 = 10 minutes
> direct  = 30 seconds
>
> Are there any tweaks we need to make to help improve performance of these
> commands when many sub-directories exist?
>
> ocfs2 nodes = 3
>
> debugfs.ocfs2 1.6.3
>         Feature Compat: 3 backup-super strict-journal-super
>         Feature Incompat: 9808 sparse inline-data xattr indexed-dirs
> discontig-bg
>         Feature RO compat: 1 unwritten
>         Dynamic Features: (0x0)
>
> _______________________________________________
> Ocfs2-users mailing list
> Ocfs2-users at oss.oracle.com
> https://oss.oracle.com/mailman/listinfo/ocfs2-users
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
http://oss.oracle.com/pipermail/ocfs2-users/attachments/20140522/89d6751e/attachment.html