From: Marcin Deranek <marcin.deranek@booking.com>
To: xfs@oss.sgi.com
Subject: Performance degradation over time
Date: Wed, 10 Oct 2012 10:51:42 +0200 [thread overview]
Message-ID: <20121010105142.148519ca@booking.com> (raw)
Hi,
We are running XFS filesystem on one of out machines which is a big
store (~3TB) of different data files (mostly images). Quite recently we
experienced some performance problems - machine wasn't able to keep up
with updates. After some investigation it turned out that open()
syscalls (open for writing) were taking significantly more time than
they should eg. 15-20ms vs 100-150us.
Some more info about our workload as I think it's important here:
our XFS filesystem is exclusively used as data store, so we only
read and write our data (we mostly write). When new update comes it's
written to a temporary file eg.
/mountpoint/some/path/.tmp/file
When file is completely stored we move it to final location eg.
/mountpoint/some/path/different/subdir/newname
That means that we create lots of files in /mountpoint/some/path/.tmp
directory, but directory is empty as they are moved (rename() syscall)
shortly after file creation to a different directory on the same
filesystem.
The workaround which I found so far is to remove that directory
(/mountpoint/some/path/.tmp in our case) with its content and re-create
it. After this operation open() syscall goes down to 100-150us again.
Is this a known problem ?
Information regarding our system:
CentOS 5.8 / kernel 2.6.18-308.el5 / kmod-xfs-0.4-2
Let me know if you need to know anything more.
Cheers,
Marcin
_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs
next reply other threads:[~2012-10-10 8:50 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-10-10 8:51 Marcin Deranek [this message]
2012-10-10 13:17 ` Performance degradation over time Stan Hoeppner
2012-10-10 14:31 ` Eric Sandeen
2012-10-11 8:33 ` Marcin Deranek
2012-10-11 9:15 ` Marcin Deranek
2012-10-14 19:31 ` Peter Grandi
2012-10-10 23:37 ` Dave Chinner
2012-10-11 8:42 ` Marcin Deranek
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20121010105142.148519ca@booking.com \
--to=marcin.deranek@booking.com \
--cc=xfs@oss.sgi.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox