Re: [OMPI users] Programming help required in Interleaving computation+communication !

2009-11-25 Thread Atle Rudshaug
souvik bhattacherjee wrote: Hi all, I'm trying to interleave computation with communication. As a result, I have resorted to using MPI with POSIX threads. Primarily, I am trying to communicate a partial vector v3 while computing an inner product v1*v2 (mod q). To give you an idea of the platf

Re: [OMPI users] Help tracing casue of readv errors

2009-11-25 Thread Atle Rudshaug
Pacey, Mike wrote: One my users recently reported random hangs of his OpenMPI application. I've run some tests using multiple 2-node 16-core runs of the IMB benchmark and can occasionally replicate the problem. Looking through the mail archive, a previous occurrence of this error seems to been su

[OMPI users] MPI_Cart_rank: Out-of-range coordinates are erroneous for non-periodic dimensions

2009-01-07 Thread Atle Rudshaug
Hi! I am trying to find the neighbor ranks in a 3D cartesian communicator. I use MPI_Cart_shift for 6 of them, but for the 12 diagonals I tried to use MPI_Cart_rank. However, only x-direction is periodic and my program crashed because of out-of-range coordinates. Then I found something strang