Understanding Jenkins builds and processes when running in parallel

[John Wadleigh]

Hello all,

I am trying to find some documentation on how Jenkins handles multiple builds on a specific node. Does it spawn separate processes? threads? How does it manage parallel builds?  And can I see these running on the OS? I have checked on our Linux OS but cannot find specific processes that seem to match the build.   We have a Linux machine with 16 CPUs, and I would like to make sure that Jenkins is using these CPUs when running 10 build jobs at the same time.  How can I monitor this better and understand it better?

Your help is appreciated,

Thanks

[Maciej Jaros]

John Wadleigh (2015-09-28 09:58):

Hello all,

I am trying to find some documentation on how Jenkins handles multiple builds on a specific node. Does it spawn separate processes? threads? How does it manage parallel builds?  And can I see these running on the OS? I have checked on our Linux OS but cannot find specific processes that seem to match the build.   We have a Linux machine with 16 CPUs, and I would like to make sure that Jenkins is using these CPUs when running 10 build jobs at the same time.  How can I monitor this better and understand it better?

AFAIK build operations are handled by JVM so you would see threads for builds there. Not sure if every build is a single thread and if they are reused in any way.

Of course build might run another operation (especially if running shell commands), which might be visible in the OS itself.

Regards,
Nux.