[Linux-cluster] Maximum number of GFS server nodes?

[Digimer]

On 01/05/2012 12:07 PM, Dax Kelson wrote:
> Looking in older Red Hat Magazine article by Matthew O'Keefe such as:
> 
> http://www.redhat.com/magazine/008jun05/features/gfs/
> http://www.redhat.com/magazine/008jun05/features/gfs_nfs/
> 
> There are references to large GFS clusters.
> 
> "For example, if 128 GFS server nodes require..." and "scalability 300+
> or more"
> 
> Why is it on RHEL6 only a max of 16 nodes is supported?
> 
> Thanks,
> Dax Kelson
> Guru Labs

Speaking as an independent; I often see people with latency issues when
they try to grow past 16 nodes when using corosync, which is the HA
cluster communication layer in RHEL 6. More specifically, DLM (the
distributed lock manager) can start to suffer from a performance
perspective as the size of the cluster grows. You may be able to go
higher, but be prepared to do a lot of network tweaking.

Also, as Steven and Adam pointed out, >16 is outside the supported size
so you will have trouble getting any official support. If you want to
try anyway, the freenode IRC channel #linux-cluster is a good place to
ask about specific problems you run into.

-- 
Digimer
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