Most discussion I have heard relates to how a running job that makes a decision, at a well defined point, to grow itself can do that. The MPI standard currently tries to cover the aspects of this which fit within a library model and leave the resource manager outside the standard. This does not seem to be your focus. Tell me if I have misunderstood. You seem to be interested in the situation where resources are added to a cluster (or maybe freed up by other jobs completing) and having a running MPI job get notified asynchronously that there are newly available resources it can make a bid for. This idea of the cluster manager pushing resources to a job without regard to where the job is in its execution would bring lots of new issues. I am not aware of anybody having made a serious attempt to even define what would be needed inside the MPI standard to let applications catch and act on an asynchronous notification like this. My first guess is that pushing an offer of additional resource would not be very hard to design into a resource manager but the MPI API side of how to react asynchronously to that offer would be very complex. Either way (Running job decides to try for more resource vs resource manager tries to volunteer more resource to running job) I think the MPI standard can not try to specify very much about how the resource manager does its part. Dick Treumann - MPI Team IBM Systems & Technology Group Dept X2ZA / MS P963 -- 2455 South Road -- Poughkeepsie, NY 12601 Tele (845) 433-7846 Fax (845) 433-8363 <snip>

As you said, That paragraph is in the context of process creating and yes! my question was about runtime reconfiguration of an MPI cluster (whole) based on dynamic application requirements. But I think that would be impossible without having a flexible resource control. When a new node joins a cluster some pre-works must be done to enable that new node act as a member of that cluster (in run time), also, some one must be informed about new resources which just have been added to the cluster by entrance of new node and I think all these preparations need that missing flexible resource manager.

Regards, Siavash_______________________________________________ mpi-22 mailing list mpi-22_at_[hidden] http://lists.mpi-forum.org/mailman/listinfo.cgi/mpi-22

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