I have added my observation to the ZWiki devoted to Zope in production environments. http://www.zope.org/Members/tseaver/Projects/HighlyAvailableZope/UnfairLinux... I don't know if this addresses all our troubles but it might be worth investigating. I was able to verify, with the example python code, that this thread thing is an issue on two of our three server; the two that exhibit unexplained restarts. The third server which does not restart also does not suffer from this thread problem. Does anyone know how to change the scheduling policy for zope/python? In the quote from the LinuxThreads FAQ there appears to be an indication that SCHED_FIFO or SCHED_RR would more precisely define the scheduling behavior. Anyone know how to do that? Would it help? There is also some indication that this issue is addressed in pthreads 0.8. I've upgraded a workstation with glibc 2.1.3, which I believe should have ptheads 0.8, and the problem still exists. Any ideas? -- ------------------------------- tonyr@ep.newtimes.com Director of Web Technology New Times, Inc. -------------------------------