Expert Advice

Linux_High_CPU_System  
Situation Description
Possible Causes
Suggested Actions
Situation Description

The percentage of processor time that is used for system calls is high. The percentage of time spent servicing user level (API) calls versus system level calls can point out whether a system's load is primarily due to running applications, or due to operating system kernel overhead. High user-level to system level ratios tend to be good and are generally considered normal.

 

Possible Causes
  1. High System CPU usage might be caused by run-away processes.
  2. Intermittent hardware failures might also cause spikes in CPU usage.
  3. Unusually high workload (transactions) on the system.

 

Suggested Actions

Find the specific processes that are spending an inordinate amount of their CPU time servicing system calls. If these are system processes, look to see if there are any available kernel patches. Check for run-away processes, or any configuration changes that can have caused System CPU usage to spike. Check /var/log/messages for signs of hardware failures. Finally, look for other signs of sudden increase in the workload, such as excessive paging. If this is due to an increase in workload, consider increasing available system resources by upgrading the system.

 

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