Hi guys,
I was hoping someone here could shed some light on OpenMPI's use of /tmp
(or, I guess, TMPDIR) and save me from diving into the source.. ;)
The background is that I'm trying to run some applications on a system
which has a flaky parallel file system which TMPDIR is mapped to - so, on
On Sat, 2008-08-16 at 08:03 -0400, Jeff Squyres wrote:
> - large all to all operations are very stressful on the network, even
> if you have very low latency / high bandwidth networking such as DDR IB
>
> - if you only have 1 IB HCA in a machine with 8 cores, the problem
> becomes even more di
> - per the "sm" thread, you might want to try with just IB (and not
> shared memory), just to see if that helps (I don't expect that it
> will, but every situation is different). Try running "mpirun --mca
> btl openib ..." (vs. "--mca btl ^tcp").
Unfortunately you were right- it did not help. Sm
Date: Sat, 16 Aug 2008 08:18:47 -0400 From: Jeff Squyres
Subject: Re: [OMPI users] SM btl slows down
bandwidth? To: Open MPI Users Message-ID:
<1197bce6-a7e3-499e-8b05-b85f7598d...@cisco.com> Content-Type:
text/plain; charset=US-ASCII; format=flowed; delsp=yes On Aug 15,
2008, at 3:32 PM,
On Aug 15, 2008, at 3:32 PM, Gus Correa wrote:
Just like Daniel and many others, I have seen some disappointing
performance of MPI code on multicore machines,
in code that scales fine in networked environments and single core
CPUs,
particularly in memory-intensive programs.
The bad performan
On Aug 13, 2008, at 7:06 PM, Yvan Fournier wrote:
I seem to have encountered a bug in MPI-IO, in which
MPI_File_get_position_shared hangs when called by multiple processes
in
a communicator. It can be illustrated by the following simple test
case,
in which a file is simply created with C IO
There are likely many issues going on here:
- large all to all operations are very stressful on the network, even
if you have very low latency / high bandwidth networking such as DDR IB
- if you only have 1 IB HCA in a machine with 8 cores, the problem
becomes even more difficult because al
It's not entirely clear that this means that it is a bug in Open MPI
-- there's not really enough information here to say where the problem
is. All that is clear is that a seg fault is happening somewhere in
LAPACK.
FWIW, I don't see MPI in the call stack of the segv at all. This
doesn'
This is allowable by the MPI API. You're specifically telling MPI "I
don't care to know when that send has completed." See the section for
MPI_REQUEST_FREE here:
http://www.mpi-forum.org/docs/mpi-11-html/node47.html#Node47
It's debatable whether that's good programming practice or not
On Fri, 15 Aug 2008, Kozin, I \(Igor\) wrote:
> Hello, I would really appreciate any advice on troubleshooting/tuning
> Open MPI over ConnectX. More details about our setup can be found here
> http://www.cse.scitech.ac.uk/disco/database/search-machine.php?MID=52
> Single process per node (ppn
10 matches
Mail list logo
