[mpich-devel] find out what processes are on the same node

[Tatiana V. Martsinkevich]

Jeff, Rob,

thank you! MPI_Comm_split_type() is what I was looking for.

Tatiana


2013/7/3 Jeff Hammond <jhammond at alcf.anl.gov>:
> https://wiki.alcf.anl.gov/parts/index.php/Implementing_a_Symmetric_Heap has an implementation of MPE_Comm_split_node that does a very simple O(Nproc) implementation of MPI_Comm_split_type(type=SHARED) using MPI_Get_processor_name.  It also shows the non-portable implementation for Cray and Blue Gene that one can use until MPI-3 is deployed on those systems.
>
> Jim Dinan wrote an O(log Nproc) implementation of MPI_Comm_split_type(type=SHARED) that I have somewhere but I don't like it because it's confusing to my small brain.
>
> Jeff
>
> ----- Original Message -----
> From: "Rob Latham" <robl at mcs.anl.gov>
> To: devel at mpich.org
> Sent: Wednesday, July 3, 2013 10:53:15 AM
> Subject: Re: [mpich-devel] find out what processes are on the same node
>
> On Wed, Jul 03, 2013 at 10:39:55AM -0500, Tatiana V. Martsinkevich wrote:
>> Hello,
>>
>> I have a couple of questions:
>>
>> 1) is there a way to find out what other processes reside in the same
>> node as my_rank from within MPICH?
>
> MPI_GET_PROCESSOR_NAME might be what you are looking for.
>
> ==rob
>
> --
> Rob Latham
> Mathematics and Computer Science Division
> Argonne National Lab, IL USA
>
> --
> Jeff Hammond
> Argonne Leadership Computing Facility
> University of Chicago Computation Institute
> jhammond at alcf.anl.gov / (630) 252-5381
> http://www.linkedin.com/in/jeffhammond
> https://wiki.alcf.anl.gov/parts/index.php/User:Jhammond
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