On Jun 23, 2016, at 8:20 AM, Saliya Ekanayake wrote:
>
> I've got a quick question. Besides theses time sharing constraints, does
> number of cores has any significance to MPI's communication decisions?
Open MPI doesn't use the number of cores available to it in any calculations /
algorithm se
Thank you, this is really helpful. Yes, the other bookkeeping threads of
Java were what I worried too.
I think I can extract a part to make a c program to check.
I've got a quick question. Besides theses time sharing constraints, does
number of cores has any significance to MPI's communication d
Java uses *many* threads, simply
ls /proc//tasks
and you will be amazed at how many threads are used.
Here is my guess,
from the point of view of a given MPI process :
in case 1, the main thread and all the other threads do time sharing, so
basically, when an other thread is working, the mai
Thank you, Gilles for the quick response. The code comes from a clustering
application, bu let me try to explain simply what the pattern is. It's a
bit long than I expected.
The program has the pattern BSP pattern with *compute()* followed by
collective *allreduce()* And it does many iterations
Can you please provide more details on your config, how test are
performed and the results ?
to be fair, you should only compare cases in which mpi tasks are bound
to the same sockets.
for example, if socket0 has core[0-7] and socket1 has core[8-15]
it is fair to compare {task0,task1} bound
Hi,
I am trying to understand this peculiar behavior where the communication
time in OpenMPI changes depending on the number of process elements (cores)
the process is bound to.
Is this expected?
Thank you,
saliya
--
Saliya Ekanayake
Ph.D. Candidate | Research Assistant
School of Informatics a
