AW: AW: AW: Hybrid MPI + Multicore + Cuda build

From: Norman Geist (norman.geist_at_uni-greifswald.de)
Date: Fri Aug 15 2014 - 00:39:36 CDT

Isn’t the right option +ppn?

 

Norman Geist.

 

Von: owner-namd-l_at_ks.uiuc.edu [mailto:owner-namd-l_at_ks.uiuc.edu] Im Auftrag
von Maxime Boissonneault
Gesendet: Donnerstag, 14. August 2014 18:53
An: Norman Geist
Cc: Namd Mailing List
Betreff: Re: AW: AW: namd-l: Hybrid MPI + Multicore + Cuda build

 

I built charm with :
./build charm++ mpi-linux-x86_64 smp --with-production -j20

I then built namd with :
./config Linux-x86_64-g++ --charm-arch mpi-linux-x86_64-smp \
       --with-fftw3 --fftw-prefix $(dirname $(dirname $(which fftw-wisdom)))
\
       --with-cuda --cuda-prefix $(dirname $(dirname $(which nvcc)))

Yet, when I run mpiexec namd +p2 it tells me

mpiexec -np 8 --bind-to-socket --npernode 8 --npersocket 4 --report-bindings
namd2 +p2 +idlepoll apoa1.namd
Reason: FATAL ERROR: Unknown command-line option +p2

However, I see that without specifying +p2, it still uses more than 1 CPU
per MPI rank.

Shouldn't the +p option work with MPI + SMP ?

Maxime

Le 2014-08-14 09:14, Norman Geist a écrit :

Looks like, ./build is interactive if you start it without arguments.
 
Norman Geist.
 
 

-----Ursprüngliche Nachricht-----
Von: owner-namd-l_at_ks.uiuc.edu [mailto:owner-namd-l_at_ks.uiuc.edu] Im
Auftrag von Maxime Boissonneault
Gesendet: Donnerstag, 14. August 2014 14:20
An: Norman Geist
Cc: Namd Mailing List
Betreff: Re: AW: namd-l: Hybrid MPI + Multicore + Cuda build
 
Hi,
That should not be a problem, since if a job uses more than one node,
we
expect it will use the nodes to their full extent. In other words, I
don't see a use case where you would want to use two half nodes instead
of one full node.
 
I've been given the pointer that building charm++ with
./build charm++ mpi-linux-x86_64 smp ....
 
should do the trick. Is that correct ?
 
 
Maxime
 
 
Le 2014-08-14 03:13, Norman Geist a écrit :

Yes its possible, but the keyword isn't "multicore" which always

indicate a

single node build, but "SMP". So you need to build your charm++ with
network+smp support ;)
 
BUT, unfortunately namd threats the +devices list for each node.

Therefore

it's not possible to assign different gpus on different nodes for the

same

job. I hacked the code to allow the +devices list to be accessed by

the

process's global rank, rather than the local rank on the node. So

it's

possible to assign a individual GPU for every process, which wouldn't

also

require a smp build. I can send you the changes I made.
 
Norman Geist.
 

-----Ursprüngliche Nachricht-----
Von: owner-namd-l_at_ks.uiuc.edu [mailto:owner-namd-l_at_ks.uiuc.edu] Im
Auftrag von Maxime Boissonneault
Gesendet: Mittwoch, 13. August 2014 18:47
An: namd-l_at_ks.uiuc.edu
Betreff: namd-l: Hybrid MPI + Multicore + Cuda build
 
Hi,
I am managing a GPU cluster. The configuration of the nodes is :
- 8 x K20 per node
- 2 x 10-core sockets per node.
 
The GPUs are run in exclusive process mode to prevent one user to
hijack
the GPU allocated to another user.
 
I would like to be able to run Namd with Cuda, with 1 MPI rank per

GPU

and 2 or 3 threads.
 
Is it possible to build namd with such hybrid support ? All I see on
the
website and documentation is either multicore or mpi, but never

both.

 
 
 
Thanks,
 
 

--
---------------------------------
Maxime Boissonneault
Analyste de calcul - Calcul Québec, Université Laval
Ph. D. en physique
 
---
Diese E-Mail ist frei von Viren und Malware, denn der avast!
Antivirus Schutz ist aktiv.
http://www.avast.com
 
 
 
--
---------------------------------
Maxime Boissonneault
Analyste de calcul - Calcul Québec, Université Laval
Ph. D. en physique
 
 
---
Diese E-Mail ist frei von Viren und Malware, denn der avast! Antivirus
Schutz ist aktiv.
http://www.avast.com
 
 
-- 
---------------------------------
Maxime Boissonneault
Analyste de calcul - Calcul Québec, Université Laval
Ph. D. en physique
---
Diese E-Mail ist frei von Viren und Malware, denn der avast! Antivirus Schutz ist aktiv.
http://www.avast.com

This archive was generated by hypermail 2.1.6 : Wed Dec 31 2014 - 23:22:43 CST