Can 64-bit Mpiexec start programs compiled for 32-bit?

[Charland, Denis]

> -----Original Message-----
> From: mpiexec-bounces at osc.edu 
> [mailto:mpiexec-bounces at osc.edu]On Behalf
> Of Tod Hagan
> Sent: Wednesday, March 22, 2006 2:05 PM
> To: 
> Subject: Can 64-bit Mpiexec start programs compiled for 32-bit?
> 
> 
> We have an Opteron cluster with Myrinet running 64-bit SuSE with
> Torque and mpichgm-1.2.6.
> 
> Jobs compiled for 64-bit get started correctly by mpiexec.
> 
> Jobs compiled for 32-bit don't get started correctly by the 64-bit
> mpiexec.
> 
> The symptom is that the jobs don't get the correct rank and size
> information. For example, a trivial program which prints the
> MPI_Comm_rank and MPI_Comm_size values compiled for 64-bit
> produces:
> 
> node 5/6
> node 4/6
> node 2/6
> node 3/6
> node 1/6
> node 0/6
> 
> The same program compiled as 32-bit and run with the 64-bit mpiexec
> produces:
> 
> node 0/1
> node 0/1
> node 0/1
> node 0/1
> node 0/1
> node 0/1
> 
> The 32-bit program works correctly when started with the 32-bit mpirun
> from mpichgm-1.2.6.
> 
> I'm unclear whether this is an mpiexec problem, a Torque problem, or
> an issue of integrating the two packages.
> 
> While we could just use the 32-bit mpirun for the 32-bit jobs, it's
> not integrated as well with Torque.
> 
> One thing I haven't yet tried is compiling mpiexec in 32-bit --
> linking with our batch system will require me to also compile 32-bit
> Torque libraries, which I was hoping to avoid.
> 
> Any advice for making mpiexec work for 32-bit jobs in this
> configuration would be greatly appreciated.
> 

Hi Tod,

We have a dual-Xeon cluster with Myrinet running 64-bit Fedora Core4 with OpenPBS 2.3.16 (the ancestor of Torque), mpiexec 0.80 and mpichmx-1.2.6. Both mpiexec and OpenPBS were compiled in 32-bit. We don't have any problem to submit both 32-bit and 64-bit jobs. I suggest that you recompile both mpiexec and Torque in 32-bit. There's no need to compile them in 64-bit.

Denis

Denis Charland, ing. | P. Eng.
Administrateur de Systèmes UNIX | UNIX Systems Administrator
Tél. | tel. (450) 641-5078     Fax (450) 641-5106
Courriel | E-mail : denis.charland at cnrc-nrc.gc.ca 

Institut des matériaux industriels | Industrial Materials Institute
Conseil national de recherches Canada | National Research Council Canada
75, de Mortagne, Boucherville, Québec, Canada, J4B 6Y4
Gouvernement du Canada | Government of Canada