[Linux-cluster] rhcs + gfs performance issues

[Gordan Bobic]

Doug Tucker wrote:
>>> 1)  Tru64 and TruCluster with Advfs from 7 years ago is simply that much
>>> more robust and mature than RHES4 and CS/GFS and therefore tremendously
>>> outperforms it...or
>> RHEL4 is quite old. It's been a while since I used it for clustering. 
>> RHEL5 has yielded considerably better performance in my experience.
> 
> Interesting.  The only way I can see upgrading is:
> 
> 1) using the upgrade options on the production node (scary, and
> downtime) or

"Upgrade" options never really worked on any OS. I wouldn't bank on it 
"just working", especially on something as complex as clustering.

> 2) do you know if RHEL5 will participate in a RHEL4 cluster?  if so, I
> could add an RHEL5 node, make it master, and then have the ability to
> upgrade the other 2 one at a time.

No, you can't mix versions. Even different package versions between the 
same distro version can cause problems.

>>> 2)  We have this badly configured.
>> There isn't all that much to tune on RHEL4 cluster-wise, most of the 
>> tweakability has been added more recently than I've last used it. I'd 
>> say RHEL5 is certainly worth trying. The problem you are having may just 
>> go away.
> 
> Bummer!

Worse, you may need to change the GFS file system options for the new 
version, so you may end up having to backup/restore the data. I don't 
think you can avoid cluster downtime for the upgrade.

Gordan