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Forum Discussion

Bernat_138012's avatar
Bernat_138012
Icon for Nimbostratus rankNimbostratus
Oct 26, 2015

High CPU utilization core 7 when ASM is active

Hi,   We did a stress test for an hour with the active ASM and after an hour with the ASM disabled. What you see is the CPU load to 100% during the first test. In the ASM it shows a CPU load of 20...
application delivery
ASM Advanced WAF
LTM
performance
security
samstep's avatar
samstep
Icon for Cirrocumulus rankCirrocumulus
Oct 27, 2015

This appears to be a known issue. Or a "Change in Behaviour" since v 11.5.1 HF4

 

F5 claim that the CPU usage chart is misleading- it is high because many ASM processes are pinned to core 7 for GUI performance reasons.

 

F5 have now pinned ASM to the highest CPU Core: Read the Solution SOL16469:

 

https://support.f5.com/kb/en-us/solutions/public/16000/400/sol16469.html

 

Also, this article will explain why you are getting High CPU spikes every 5 minutes:

 

https://support.f5.com/kb/en-us/solutions/public/15000/600/sol15606.html