Hmmm...I don't understand what you just said, but it definitely sounds -ugly-! 
:-)

I'll take your word for it - we may have to provide a lower performance version 
for such oddball purposes, and offer a higher capability version for everyone 
else. I'll see if I can keep a single version, though, assuming the code 
doesn't get too convoluted so as to become unmaintainable.

Otherwise, I'll branch it and "freeze" a non-threaded version for the unusual 
case.

Thanks!

On Oct 12, 2010, at 8:51 AM, Kenneth Lloyd wrote:

> In certain hybrid, heterogeneous HPC configurations, mpirun often cannot or
> should not be threaded through the OS under which OpenMPI runs. The primary
> OS and MPI can configure management nodes and topologies (even other MPI
> layers) that subsequently spawn various OSes and other lightweight kernels.
> These share memory spaces and indirectly access the program stacks in
> various devices.  
> 
> In short, yes, there are environments where this would cause a problem.
> 
> ==================
> Kenneth A. Lloyd
> Watt Systems Technologies Inc.
> 
> 
> -----Original Message-----
> From: devel-boun...@open-mpi.org [mailto:devel-boun...@open-mpi.org] On
> Behalf Of Barrett, Brian W
> Sent: Tuesday, October 12, 2010 8:24 AM
> To: Open MPI Developers
> Subject: Re: [OMPI devel] Threading
> 
> On Oct 11, 2010, at 11:41 PM, Ralph Castain wrote:
> 
>> Does anyone know of a reason why mpirun can -not- be threaded, assuming
> that all threads block and do not continuously chew cpu? Is there an
> environment where this would cause a problem?
> 
> We don't have any machines at Sandia where I could see this being a problem.
> 
> Brian
> 
> --
>  Brian W. Barrett
>  Dept. 1423: Scalable System Software
>  Sandia National Laboratories
> 
> 
> 
> 
> 
> _______________________________________________
> devel mailing list
> de...@open-mpi.org
> http://www.open-mpi.org/mailman/listinfo.cgi/devel
> 
> _______________________________________________
> devel mailing list
> de...@open-mpi.org
> http://www.open-mpi.org/mailman/listinfo.cgi/devel


Reply via email to