[Linux-cluster] DLM tuning
Bryn M. Reeves
bmr at redhat.com
Thu Jan 26 14:18:19 UTC 2012
-----BEGIN PGP SIGNED MESSAGE-----
On 01/25/2012 09:00 PM, Digimer wrote:
> Hi all,
> EL6 DLM question. Beginning adventures in DLM tuning... :)
> I am trying to optimize DLM for use on nodes which can hit the
> disks hard and fast. Specifically, clustered LVM with many LVs
> hosting many VMs where the VMs are simultaneously disk i/o
> intensive. I am testing though with bonnie++ to induce a high load
> on a GFS2 partition though.
Wouldn't it be more useful to test the clustered LVM scenario (e.g.
using a block device benchmark tool to simulate VM I/O load)?
GFS2 and clvmd use the locking service in quite different ways - in
particular I/O on a GFS2 file system involves locking operations but
this is not true for clvm volumes unless they use a cluster aware
device-mapper target like cmirror.
I'd only expect DLM performance to become a consideration here if
there were many clustered LVM operations taking place on different
nodes at the same time.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.11 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/
-----END PGP SIGNATURE-----
More information about the Linux-cluster