10.5 HP StoreVirtual Storage User Guide (AX696-96269, March 2013)

17 Monitoring performance
The Performance Monitor provides performance statistics for iSCSI and storage system I/Os to
help you and HP support and engineering staff understand the load that the SAN is servicing.
The Performance Monitor presents real-time performance data in both tabular and graphical form
as an integrated feature in the CMC. The CMC can also log the data for short periods of time
(hours or days) to get a longer view of activity. The data will also be available via SNMP, so you
can integrate with your current environment or archive the data for capacity planning. See
“Configuring SNMP” (page 95).
As a real-time performance monitor, this feature helps you understand the current load on the SAN
to provide additional data to support decisions on issues such as the following:
• Configuration options (Would network bonding help me?)
• Capacity expansion (Should I add more storage systems?)
• Data placement (Should this volume be on my SATA or SAS cluster?)
The performance data does not directly provide answers, but will let you analyze what is happening
and provide support for these types of decisions.
These performance statistics are available on a cluster, volume, and storage system basis, letting
you look at the workload on a specific volume and providing data like throughput, average I/O
size, read/write mix, and number of outstanding I/Os. Having this data helps you better understand
what performance you should expect in a given configuration. Storage system performance data
will allow you to easily isolate, for example, a specific storage system with higher latencies than
the other storage systems in the cluster.
Prerequisites
• You must have a cluster with one or more storage systems and one or more volumes connected
via iSCSI sessions.
• All storage systems in the management group must have LeftHand OS software version 8.0
or later installed. The management group version on the Registration tab must show 8.0 or
later.
• A server must be accessing a volume to read data, write data, or both.
Introduction to using performance information
The Performance Monitor can monitor dozens of statistics related to each cluster.
The following sections offer some ideas about the statistics that are available to help you manage
your SAN effectively. These sections cover just a few examples of common questions and issues,
but they are not an exhaustive discussion of the possibilities the Performance Monitor offers.
For general concepts related to performance monitoring and analysis, see “Performance monitoring
and analysis concepts” (page 224).
What can I learn about my SAN?
If you have questions such as these about your SAN, the Performance Monitor can help:
• What kind of load is the SAN under right now?
• How much more load can be added to an existing cluster?
• What is the impact of my nightly backups on the SAN?
• I think the SAN is idle, but the drive lights are blinking a lot. What is causing that?
214 Monitoring performance