Verifying the Activity Generated by a LUN

In order to understand the high activity of a disk array, it is important to identify the LUNs (or virtual disks in HP EVA terminology) generating the heaviest I/Os. The SAN administrator can then check with the system administrator whether the reported activity may be considered a normal behavior.

The ReadByteRate and WriteByteRate parameters of the Virtual Disk instances expose the data throughput for each LUN, while parameters such as CacheReadByteRate, FlushByteRate, MirrorByteRate, and PrefetchByteRate provide more in-depth details about the internal data traffic associated with each LUN (cache traffic and mirroring traffic).

Virtual Disks Parameters

When the system or application that relies on a LUN experiences slow response times, it may become interesting to compare the ReadResponseTime and WriteResponseTime parameters of the LUN with different instances of the Virtual Disk class to see whether the LUN actually delivers slower performance than the other LUNs.