vSAN vSAN

vSAN Performance Diagnostics

I am excited to announce that launch of vSAN Performance diagnostics. This feature will enable faster performance troubleshooting and when burning in a cluster with performance tests to understand how you can increase the IOPS or lower the storage latency and what is your bottleneck within the host.

Performance diagnostics analyzes previously executed benchmarks. It detects issues, suggests remediation steps, and provides supporting performance graphs for further insight. You will select the desired benchmark goal and a time range during which the benchmark ran. The analysis may take some time depending on the cluster size and the time range chosen. It should be noted that performance diagnostics are not expected to be used for general evaluation of performance on a production vSAN cluster.

In my lab, I ran a number of quick sanity check benchmarks on a small hybrid cluster using the built in vSAN Health UI performance testing tool. Note for larger scale, and more realistic benchmarks VMware recommends testing using HCIBench as it can simulate more realistic load as well as has integration with the Performance Diagnostics functionality.

 

A customer will need to enable the vSAN performance service (Disabled by default). Also as a requirement, a customer will need to enable the Customer Experience Improvement Program (this is enabled by default as of vSAN 6.2). A shortcut to re-enable this can be found in the health UI menu.

More information about this feature can be found on storage hub.