We're starting to see customers who have FC SANs but I'm getting the idea that some of them really don't understand very well what they're good at and what they're not. We're seeing them take our database apps and configure the data drives to be on the SAN-- but that means a lot of little disk I/O transactions over the connection during queries, etc. And this is going to a centralized FC SAN that is being shared by just about everything-- dozens of servers at least.
It's my understanding that FC SANS may have great transfer rates, but their LATENCY may not be all that great. Is that correct? On the other hand, if we have a multi-server datawarehouse app, using FC to move multi-gigabyte database files from one server to the next might be a pretty good scheme. But this is all pretty new to me. Ignoring latency for the time being, are FC transfer rates better than locally attached disk drives? If so, I would think this is simply because FC transfer rate is better than SATA. Customers are deciding to go to SAN without talking to us, and some of our apps are seriously disk-bound because of the database operations. But I can't hit them with a clue stick until I become a little less ignorant about it myself...