On 10/21/2011 09:44 AM, Henning Fehrmann wrote: > Hi Prentice, > > On Fri, Oct 21, 2011 at 09:10:18AM -0400, Prentice Bisbal wrote: >> Beowulfers, >> >> I have a question that isn't directly related to clusters, but I suspect >> it's an issue many of you are dealing with are dealt with: users using >> the screen command to stay logged in on systems and running long jobs >> that they forget about. Have any of you experienced this, and how did >> you deal with it? >> >> Here's my scenario: >> >> In addition to my cluster, we have a bunch of "computer servers" where >> users can run the programs. These are "large" boxes with more cores >> (24-32 cores) and more RAM (128 - 256 GB, ECC) than they'd have on a >> desktop top. >> >> Periodically, when I have to shutdown/reboot a system for maintenance, >> I find a LOT of shells being run through the screen command for users >> who aren't logged in. The majority are idle shells, but many are running >> jobs, that seem to be forgotten about. For example, I recently found >> some jobs running since July or August that were running under the >> account of someone who hasn't even been here for months! >> >> My opinion is these these are shared resources, and if you aren't >> interactively using them, you should log out to free up resources for >> others. If you have a job that can be run non-interactively, you should >> submit it to the cluster. >> >> Has anyone else here dealt with the problem? >> >> I would like to remove screen from my environment entirely to prevent >> this. My fellow sysadmins here agree. I'm expecting massive backlash >> from the users. > > I wouldn't deinstall screen. It is a useful tool for many things and > there are alternatives doing the same. Instead one could enforce a > maximum CPU time a job can take by setting ulimits. > > Have you thought about queueing systems like condor or SGE?
Yes, I have cluster that uses SGE, and we allow users to run serial jobs (non-MPI, etc.) there, so there is no need for them to use screen to execute long-running jobs. Hence my frustration. Prentice _______________________________________________ Beowulf mailing list, [email protected] sponsored by Penguin Computing To change your subscription (digest mode or unsubscribe) visit http://www.beowulf.org/mailman/listinfo/beowulf
