Jenkins : Build is hanging

This document attempts to explain what information we need to fix the build hang problem, if you experience one.

  • See Obtaining a thread dump to obtain a thread dump.
  • I/O in Java is fundamentally synchronous and non-interruptible. So if a build is blocked inside Jenkins while performing an I/O (for example, reading from the network), there's just no way to kill such a thread. Check the thread dump in the 1st step and see if that's the case. That said, even if you find this to be the case, please report it to us so that we know where this problem tends to happen (which might allow us to replace such non-interruptible I/O with an interruptible I/O.)

If you find the hang issues that you believe is a bug in Jenkins, please open a bug in the bug tracker, and attach those thread dump information. If someone has already filed an issue, please just add your thread dumps as additional attachments, as more information helps us resolve the problem quicker.