It seems that this reproduction case only happens after the system has been used for some unknown amount of time. At that point, fork() hangs can be triggered at will. If the instance is rebooted, the test case no longer causes hangs.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is a direct subscriber. https://bugs.launchpad.net/bugs/708920 Title: Strange 'fork/clone' blocking behavior under high cpu usage on EC2 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs