[Gluster-users] Problem: Gluster performance too high..

[Jeff Darcy]

On 03/29/2012 03:50 PM, Harry Mangalam wrote:
> You make a good point - I'm more of a biologist gone to to the dark side than a
> formally trained network guy. The cluster is in fact a distributed one - some
> of the cluster workers are in a remote building VLAN'ed into the main group,
> and the rest are on the main cluster network. From my understanding of the
> cluster networking, there are a number of 24- and 48- port stacked switches
> providing ports to the worker nodes, as well as to the gluster servers.
> 
> My assumption was that at some point there would be a 1Gb bottleneck, but if
> the packets were switched all the way thru, there would be a theoretical max
> related the number of gluster-server Gb ports (4). So until I approach 4Gb/s, I
> guess I wouldn't necessarily see this bottleneck. Is that correct?

Pretty much.  Usually the bottleneck will be either the bandwidth between
switches (even many GigE switches have one or two 10GbE uplink ports).  It used
to be that lower-end switches might only have 5Gb/s or so of internal
bandwidth, but that's pretty unlikely to be an issue nowadays.  In your case,
if you have four servers connected at 1Gb/s each then 4Gb/s (500MB/s) is likely
to be the real limit.