Q: What latency thresholds make good starting points for invoking VMware Storage DRS?

A:Storage DRS, a new feature in VMware vSphere 5, can be tasked with the responsibility of load balancing virtual machine (VM) disk files with the goalof reducing storage I/O latency. This reduction can have a significant impact on overall VM performance. When enabling Storage DRS, however, you mustidentify a threshold in milliseconds at which its services begin taking action.

Although the default setting for I/O latency is set to 15 milliseconds, your threshold will be different based on storage architecture and the types ofdisks being used. At a recent VMworld session on storage I/O control, the following thresholds were offered as starting points for where this slidershould be set:

Obviously, your mileage may vary.