Dell PE R320
Windows Server 2012 R2
Hyper-V Role w/ 4 VM's
IDRAC 7 / BIOS Version 2.3.3
1) Intel(R) Xeon(R) CPU E5-2420 v2 @ 2.20 GHz E5 220 MHz
Issue/Symptoms: System online in production approximately a month. No issues during that time. One morning we received SCOM alerts on high CPU. Upon investigation, the Hyper-V Host CPU was averaging 25% with spikes to 50%, the VM's CPU average 80% spiking to 100%. Memory is not an issue on either Host or VM's. No system changes were identified. System performance severely degraded, users report slow access to network shares, users directories.
Troubleshooting: Rebooted (several times), upgrading NIC Firmware/Drivers, uninstalling McAfee, Backup Exec and the SCOM Monitoring Agent with no results. We were leaning towards it being a VM issue on the host so we opened a case with Microsoft. Throughout 10+ hours we supplied traces using Perfmon, Process Explorer and XPerf which were all inconclusive. It was grueling getting the traces and reports to complete because of the degraded system performance.
Resolution: Logging into the IDRAC, booting to the BIOS, select System Profile, change the profile from Performance per Watt to Performance.
Immediate results... Hyper V Host CPU dropped to 0% - 4% average. It was like a new system.
The posts in this forum by user "LSLC" assisted immensely towards a resolution.