we have LOB saying that they are having performance issues for their servers connected to the DMX. Could any one please let me know what are the things we need to check on the DMX using Symcli and also do we need to check the IOPS, Port Statistics and etc. and also could any one let me know what are the things we need to consider when analyzing the performance issues.
I would really appreciate if you can provide me this info.
What kind of host OS is this? If Windows host, turn on data collection for perfmon (LogicalDisks & PhysicalDisks), Check read and write service times. For Unix based hosts check iostat and/or "sar -d" data to see what the service time and IO load looks like. As Quincy56 mentioned, if the service times are high (>usual (good day) or >25ms) then definitely plan to spend some looking at the DMX. Also check for queued IOs. If you have the iostat/sar/perfmon data, I can help by using some of the tools i have for this.
I think the first and most important question is to the LOB reporting the problem. They need to let you know what evidence they have that the storage is the root of the problem. What are they actually seeing.
Then the investigation should start at the server. If the LOB have valid complaints and the server investigation supports the belief that the Storage is involved, the server investigation results should be able to direct you to the most appropriate things to check on the DMX.
There are a number of steps that EMC goes through when troubleshooting performance issues.
Firstly the host configuration
Are the latest HBA drivers and firmware and OS patches recommended by EMC applied along with the recommended multipathing software
For OSes that rely on partition offsets then are these correct for optimal performance
Next the switches
How many switches are involved in the communication to the storage
are there any issues reported on the ports facing the HBAs or the ports facing the storage
are there any issues reported on any ISLs in the fabric (even if they do not appear to be on the route between host and storage)
Is switch firmware at recommended / supported levels
Finally the storage
We would possibly need to engage a local Performance expert to analyze the behaviour seen on the storage - gathering stp data for DMX/V-Max or NAR files and SPCollects for Clariion
This last step should only be carried out once everything else has been eliminated
Obviously this would need to be done in the context of a Service Request.
Vajinap
47 Posts
352
0
Posted June 23rd, 2009 09:00