Today we diagnosed the cause of a Periodic slowness issue: see here.
Dell OpenManage Server Administrator seems to have been causing hourly slowness. It would occasionally peg one of the CPUs for upwards of two minutes. Disabling it drastically improved the performance of the SQL Server.
The server hardware:
- Dell R710
- Dual Quad Core 2.9GHz Processors
- 96GB Memory
- 2 Disk RAID 1 SAS System Disk (Internal)
- 4 Disk RAID 10 SAS Log Disk (Internal)
- 14 Disk RAID 10 SAS Data Disk (External DAS MD1000)
- Windows 2008 Enterprise R2 x64
We installed the OS using Dell OpenManage Server Assistant, so I assume that it was correctly configured.
For now we have disabled OMSA to alleviate the performance issues it was causing, but I'd like to be able to re-enable it.
Has anyone had a similar experience that can shed a little light on the nature of this problem?
Yes I have had the same problems with OMSA before, and in some instances it has been in an infinite loop and I have had to kill the process to restore the server to normal operation.
I never found a resolution for the issue (google returns lots of posts like this one and KB articles for VMware and Xen discussing a similar problem).
In my environment I can afford to have it run normally (<5 mins of 100%) but scripted up a tool to look for processes that had run at 90% (or higher) for more than 5 minutes.
I've seen that OpenManage can actually crash Window's SNMP service. It's quite depressing, really.