Re: [OMPI users] Is Iprobe fast when there is no message to recieve

2009-10-03 Thread Jeff Squyres
Keep in mind that MPI says you do have to eventually receive the message -- so just checking if it's there is not enough (eventually). Iprobe is definitely one way. You could also post a non-blocking receive (persistent or not) and MPI_TEST to see if it has completed. However, if the

Re: [OMPI users] Are there ways to reduce the memory used by OpenMPI?

2009-10-03 Thread Jeff Squyres
On Oct 1, 2009, at 2:56 PM, Blosch, Edwin L wrote: Are there are tuning parameters than I can use to reduce the amount of memory used by OpenMPI? I would very much like to use OpenMPI instead of MVAPICH, but I’m on a cluster where memory usage is the most important consideration. Here are

Re: [OMPI users] MPI_Comm_accept()/connect() errors

2009-10-03 Thread Jeff Squyres
On Oct 1, 2009, at 7:00 AM, Blesson Varghese wrote: The following is the information regarding the error. I am running Open MPI 1.2.5 on Ubuntu 4.2.4, kernel version 2.6.24 Is there any chance that you can upgrade to the Open MPI v1.3 series? -- Jeff Squyres jsquy...@cisco.com

Re: [OMPI users] job fails with "Signal: Bus error (7)"

2009-10-03 Thread Jeff Squyres
Bus error usually means that there was an invalid address passed as a pointer somewhere in the code -- it's not usually a communications error. Without more information, it's rather difficult to speculate on what happened here. Did you get corefiles? If so, are there useful backtraces

Re: [OMPI users] use additional interface for openmpi

2009-10-03 Thread Jeff Squyres
On Sep 29, 2009, at 9:58 AM, wrote: > Open MPI should just "figure it out" and do the Right Thing at run- > time -- is that not happening? you are right it should. But I want to exclude any traffic from OpenMPI communications, like NFS, traffic from other

Re: [OMPI users] Is Iprobe fast when there is no message to recieve

2009-10-03 Thread Ashley Pittman
On Sat, 2009-10-03 at 07:05 -0400, Jeff Squyres wrote: > That being said, if you just want to send a quick "notify" that an > event has occurred, you might want to use a specific tag and/or > communicator for these extraordinary messages. Then, when the event > occurs, send a very short