[mpich-discuss] SMP and mpd.hosts

[Rajeev Thakur]

Did you look at Sec 5.1.7 (pg 18) of the installation guide?
http://www.mcs.anl.gov/research/projects/mpich2/documentation/files/mpich2-1.1-installguide.pdf 

It tells you how to run MPD on SMPs.

On a single machine, you can simply do "mpd &" or "mpdboot -n 1".

Rajeev


> -----Original Message-----
> From: mpich-discuss-bounces at mcs.anl.gov 
> [mailto:mpich-discuss-bounces at mcs.anl.gov] On Behalf Of 
> Torquil Macdonald Sørensen
> Sent: Tuesday, June 30, 2009 11:01 AM
> To: mpich-discuss at mcs.anl.gov
> Subject: [mpich-discuss] SMP and mpd.hosts
> 
> Hi all,
> 
> I would like to ask for some help concerning the use of 
> MPICH2 1.1 on a 
> dual-core machine with Linux. My mpich2 innstallation uses 
> the nemesis 
> communication device, which I thought was able to utilise 
> both cores, in 
> addition to communicate through the network.
> 
>  From before (maybe from mpich1?) I had a mpd.hosts file with the 
> following syntax:
> 
> dagda.uio.no:2
> #styx.uio.no:2
> 
> where the :2 was to indicate the number of CPUS. styx.uio.no is 
> commented out because this time I want two processes to run on 
> dagda.uio.no. But I am no longer sure of this syntax since I 
> cannot find 
> it in the documentation. I was hoping that the following would work:
> 
> $ mpdboot -n 2
> $ mpiexec -n 2 ./Executable
> 
> However, mpdboot complains:
> 
> "totalnum=2  numhosts=1
> there are not enough hosts on which to start all processes"
> 
> What it the common method to run a program so that it will be able to 
> distribute itself across several cpu-cores in one machine, and also 
> across the network, if I e.g. decomment styx.uio.no and use 
> -n 4 in the 
> above commands?
> 
> Best regards
> Torquil Sørensen
>