Jenkins running at very high CPU usage

Question

I recently upgraded from Jenkins 1.6 to 2.5. After I did this, I noticed very high CPU usage, sometimes over 300% (there are only 4 cores, so I don\'t think it could go over 40

Answer 1

Whenever a request comes in, Jenkins will spawn some threads to serve the request. After upgrading Jenkins, it might have invoked at high throttle at that time. Plz check the CPU and memory usage of Jenkins server while the following scenarios :

• Jenkins is idle and no other apps are running on the server.
• Scheduled a build and no other apps are running on the server.

And compare the behaviors which could help you out to determine whether Jenkins or running jenkins in parallel with other apps are really making trouble.

As @vlp said, try to monitor the jenkins application via JVisualVM with Jstad configuration to hook in. Refer this link to Configure JvisualVM with Jstad.