From Bugzilla Helper: User-Agent: Mozilla/4.76C-CERN UNIX gryphn 45 [en] (X11; U; Linux 2.4.2-2 i686) Description of problem: After some time of running under heavy nfs traffic a process on one or more of the nfs client nodes starts consuming 100% of one cpu but not seeming to progress. Doing kill -9 <pid> as root does nothing. The system otherwise continues to respond. Nothing unusual shows up in /var/log/messages. Doing a normal reboot proceeds as usual, and the rebooted system is idle again. When the stuck process is running, /proc/loadavg reports 2.0 runnable processes. Running top shows 100% of one cpu devoted to running the stuck job. This process is running 100% system-time. It does not respond to signals. Top reports this process as RW (runnable and swapped). Its sizes (from top) are all zero as expected for swapped-out processes. Version-Release number of selected component (if applicable): 2.4.2-2smp kernel. Test node is running stock i686 kernel. Other nodes run a diskless (IP-autoconfig + nfs-root) build and show same behavior. I have not seen it on my Athlon-smp nodes so far. How reproducible: Sometimes Steps to Reproduce: 1. Run several i/o bound (nfs) jobs on the cluster, loading the net/server 2. Log onto one of the client nodes and start something (eg. compiler) 3. Watch top to see the process jump to 100% system-mode usage. Actual Results: At some point the job will get stuck. Sequential shutdown (with /etc/rc.d/init.d/* stop) of everything (except network) fails to unstick it. Reboot works. Expected Results: process should have finished normally, or at least responded to kill -9 <pid> from superuser. Additional info:
Should have been fixed a long time ago by errata kernel. If not re-open.