[Linux-cluster] Performance tunning

[David Teigland]

On Thu, Feb 17, 2005 at 10:47:55AM -0500, Manuel Bujan wrote:
> Hello,
> 
> Is there anyway to improve the performance of a cman based gfs cluster 
> installation tunning some of its parameters ?
> 
> We are using the dlm style locking mechanism in a two node 100 GB shared 
> gfs cluster with a DELL powervault 220s storage.
> We already disabled the atime updates and  the quotas_account but the gain 
> in performance is not too significant.
> 
> Any other hints ?

Look at /proc/cluster/lock_dlm/drop_count

It's 50000 by default and increasing it could possibly improve things,
or disable it altogether by setting to zero.
e.g.  echo "0" >> /proc/cluster/lock_dlm/drop_count

You need to change this prior to mounting gfs on each node.  When
non-zero, GFS/lock_dlm tries to keep the number of locks held locally
below this level which limits the caching gfs can do.  When zero, no
limiting is attempted.

-- 
Dave Teigland  <teigland at redhat.com>