On Apr 27, 2011, at 12:38 PM, Michael Di Domenico wrote: > On Wed, Apr 27, 2011 at 2:25 PM, Ralph Castain <r...@open-mpi.org> wrote: >> >> On Apr 27, 2011, at 10:09 AM, Michael Di Domenico wrote: >> >>> Was this ever committed to the OMPI src as something not having to be >>> run outside of OpenMPI, but as part of the PSM setup that OpenMPI >>> does? >> >> Not that I know of - I don't think the PSM developers ever looked at it. >> >>> >>> I'm having some trouble getting Slurm/OpenMPI to play nice with the >>> setup of this key. Namely, with slurm you cannot export variables >>> from the --prolog of an srun, only from an --task-prolog, >>> unfortunately, if you use a task-prolog each rank gets a different >>> key, which doesn't work. >>> >>> I'm also guessing that each unique mpirun needs it's own psm key, not >>> one for the whole system, so i can't just make it a permanent >>> parameter somewhere else. >>> >>> Also, i recall reading somewhere that the --resv-ports parameter that >>> OMPI uses from slurm to choose a list of ports to use for TCP comm's, >>> tries to lock a port from the pool three times before giving up. >> >> Had to look back at the code - I think you misread this. I can find no >> evidence in the code that we try to bind that port more than once. > > Perhaps i misstated, i don't believe you're trying to bind to the same > port twice during the same session. i believe the code re-uses > similar ports from session to session. what i believe happens (but > could be totally wrong) the previous session releases the port, but > linux isn't quite done with it when the new session tries to bind to > the port, in which case it tries three times and then fails the job
Actually, I understood you correctly. I'm just saying that I find no evidence in the code that we try three times before giving up. What I see is a single attempt to bind the port - if it fails, then we abort. There is no parameter to control that behavior. So if the OS hasn't released the port by the time a new job starts on that node, then it will indeed abort if the job was unfortunately given the same port reservation. > > _______________________________________________ > users mailing list > us...@open-mpi.org > http://www.open-mpi.org/mailman/listinfo.cgi/users
