On Fri, Jan 27, 2012 at 01:04:39PM +0000, Dan Bretherton wrote: > I need to buy a bigger GigE switch for my GlusterFS cluster and I am > trying to decide whether or not a much more expensive one would be > justified. I have limited experience with networking so I don't > know if it would be appropriate to spend ?500, ?1500 or ?3500 for a > 48-port switch. Those rough costs are based on a comparison of 3 > Dell Powerconnect switches: the 5548 (bigger version of what we have > now), the 6248 and the 7048. If you already have 5524s then they are apparently stackable using a HDMI cable, have you tried that? I have bad experience with Powerconnect 5524's, but maybe you're just not tickling the same bugs I found (e.g. multicast problems, failing to learn MAC addresses) Haven't had these same problems with Netgear GSM7224V2, but then maybe they have a different set of bugs :-) > Some of the users' > applications do lots of small reads and writes, and they do run much > more slowly if all the servers are not connected to the same switch, > as is the case now while I don't have a big enough switch. If it's consistently a little slower for each individual file read and written, then it sounds like this usage pattern is extremely latency-sensitive. If it seems to be in bursts then maybe you are getting small amounts of packet loss, which is causing TCP to back off. Side note: if you are latency-sensitive then don't even think about using 10Gig over RJ45 - it actually has a higher latency than 1G. But 10Gig over SFP+ is fine. Regards, Brian.
