vSphere High Performance Cookbook

Avoiding the use of SDRS I/O Metric and array-based automatic tiering together

While we can employ array-based automatic LUN tiering and VMware Storage DRS, we need to disable the I/O Metric-based calculation in SDRS. So, in this way we would not employ both of them doing the same job. Now let us see what it does in the back end.

SDRS triggers action on either capacity and/or latency. Capacity stats are constantly gathered by vCenter, where the default threshold is 80 percent. I/O load trend is evaluated (by default) every eight hours, based on the past day's history; the default threshold is 15ms. This means that the Storage DRS algorithm will be invoked when these thresholds are exceeded. Now in the case of "utilized space", this happens when ...