HP c-Class Performance Tuning manual CPU thermal throttling or auto-idling

Correctable Error Reporting: enabled

Non-fatal Error Reporting: enabled

Unsupported Request Reporting: enabled Current status: 0x0000

Correctable Error(s): None

Non-Fatal Error(s): None

Fatal Error(s): None

Unsupported Type(s): None

Current link capabilities: 0x02014501 Maximum link speed: 2.5 Gb/s Maximum link width: 16 lanes

Current link capabilities: 0x00001041 Link speed: 2.5 Gb/s

Link width is 4 lanes

ioDrive 01:00.0 Firmware 11791

CPU thermal throttling or auto-idling

Issue

Current-generation CPUs monitor themselves for thermal overheat. If the CPU is running on the edge of its manufacturer-specified thermal tolerance, the CPU will reduce its clock rate to keep from overheating. This reduces overall system performance, including IO Accelerator performance.

Some systems have a CPU idle detector installed as well. This decreases the clock rate of the CPU under low load to conserve power, but it also decreases overall system performance.

Solution

To detect a CPU running at a slower rate, inspect the contents of the /proc/cpuinfo file (in the Linux kernel) for discrepancies between the speed reported by the model and the current running speed. You must perform this inspection for each of the CPUs included in the listing.

Below is sample output of a system that has throttled from 2.66 GHz to 1 GHz.

processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 15
model name : Intel (R) Xeon (R) CPU	5150 @ 2.66GHz
stepping : 5
cpu MHz : 1000.382
cache size : 4096 KB
--snip--

Debugging performance issues 13