I/O Analyzer is a virtual appliance solution for storage performance measurement for large scale ESX clusters deployment.
vBenchmark is a simple application that allows you to measure key datacenter operational and efficiency metrics. Simply connect to your vCenter Server hosts and the application provides a snapshot of these metrics for your entire virtualized environment.
IOBlazer is a multi-platform storage stack micro-benchmark. IOBlazer runs on Linux, Windows and OSX and it is capable of generating a highly customizable workload.