Benchmarking storage performance
One common question is, is the storage performing properly? One way to tell is to benchmark it.
there are lots of tools to run benchmarks, but you want a tool that will allow you to simulate you production workload as close as possible. This includes read/write mixture, %random vs sequential, block size, cache hit ratio and even wait time. To achieve this, there are a few good tools to use.
IOMeter is an open source tool that provides a lot of flexibility
IORate is a tool by EMC that gives you even more options, including adjusting the cache hit ratio