Home / server / Questions / 108409
In Process
yvess
Asked: 2010-02-02 09:04:02 +0800 CST

For kvm host images. GFS2 or OCFS2 with drbd8?

  • 772

I want a shared filesystem on top of drbd8 on two nodes. The servers run ubuntu 9.10.

I googled a lot, but couldn't find an clear trend what the web community prefers. It's seems that OCFS2 is more used at the moment.

Which filesystem is more reliable, faster? GFS2 or OCFS2? Is the linux community going more towards GFS2 or OCFS2? Which of this two is better supported by ubuntu 9.10?

Are there better (or more common) alternatives?

kvm-virtualization drbd gfs ocfs2

3 Answers

  1. We use GFS2/rgmanager/DRBD and KVM for our cloud infrastructure.

    I don't know what sort resource manager OCFS2 has; but gfs2 rgmanager is great and supports live migration; which work flawlessly.

    I have been meaning to try out GPFS but have not got around to testing this; I was going to setup gpfs nodes in the existing kvm/gfs2 setup as vm guests.

    Overall: Very reliable, some performance concerns with GFS2 locking between nodes even with rate limiting disabled.

    • One node plock test

    [root@core-01 ~]# ./ping_pong /gfs2-00/test 3

    2159 locks/sec

    • On both nodes

    [root@core-01 ~]# ./ping_pong /gfs2-00/test 3

    1336 locks/sec

    [root@core-02 ~]# ./ping_pong /gfs2-00/test 3

    1333 locks/sec

    • One node pclock rw test "./ping_pong -rw /gfs2-00/test 3"

    [root@core-01 ~]# ./ping_pong -rw /gfs2-00/test 3

    2192 locks/sec

    • Two node pclock rw test "./ping_ping -rw /gfs2-00/test 3"

    [root@core-01 ~]# ./ping_pong -rw /gfs2-00/test 3

      2 locks/sec

    [root@core-02 ~]# ./ping_pong -rw /gfs2-00/test 3

      2 locks/sec

    I attempted to document some of our work:

    http://wiki.samba.org/index.php/6.0:_DRBD#6.5._DRBD_8.0_GFS2_Primary.2FPrimary_Clustered_Filesystem

    • 1

  2. I can't talk for everyone but certainly we're very happy with OCFS2, whether that be on bare-metal OEL or within ESX VMs.

    • 0

  3. I tested both GFS2 and OCFS2 on a drdb Ubuntu-9.04 storage server pair, with a pair of Ubuntu-9.04 servers mounting the kvm images via NFS and iSCSI.

    I gave up configuring GFS2 as the instructions for OCFS2 worked almost out of the box for me. I still don't know why GFS2 did not work as I have set it up in a pair of virtual machines since then without a problem.

    We are quite happy with the performance of drbd + OCFS2 + kvm. We did run into problems early on with short drbd timeouts though. If we used qcow2 expand on write images, then we would get intermittent VM crashes under high load. Since converting the images to raw we have not had any problems.

    • 0