Re: [OMPI users] Job distribution on many-core NUMA system

2009-09-01 Thread Eugene Loh
A. Austen wrote: On Fri, 28 Aug 2009 10:16 -0700, "Eugene Loh" wrote: Big topic and actually the subject of much recent discussion. Here are a few comments: 1) "Optimally" depends on what you're doing. A big issue is making sure each MPI process gets as much memory bandwidth

Re: [OMPI users] Job distribution on many-core NUMA system

2009-08-28 Thread A. Austen
On Fri, 28 Aug 2009 10:16 -0700, "Eugene Loh" wrote: > Big topic and actually the subject of much recent discussion. Here are > a few comments: > > 1) "Optimally" depends on what you're doing. A big issue is making > sure each MPI process gets as much memory bandwidth (and cache and other >

Re: [OMPI users] Job distribution on many-core NUMA system

2009-08-28 Thread Eugene Loh
Big topic and actually the subject of much recent discussion. Here are a few comments: 1) "Optimally" depends on what you're doing. A big issue is making sure each MPI process gets as much memory bandwidth (and cache and other shared resources) as possible. This would argue that processes

[OMPI users] Job distribution on many-core NUMA system

2009-08-28 Thread A. Austen
Hello all. I apologize if this has been addressed in the FAQ or on the mailing list, but I spent a fair amount of time searching both and found no direct answers. I use OpenMPI, currently version 1.3.2, on an 8-way quad-core AMD Opteron machine. So 32 cores in total. The computer runs a modern