My apologies, So hydra is in effect a super user? Eibhlin ________________________________________ From: Pavan Balaji [[email protected]] Sent: 13 June 2013 16:02 To: Lee, Eibhlin Cc: [email protected] Subject: Re: [mpich-discuss] Running an mpi program that needs to access /dev/mem Please don't drop the mailing list from the cc. You can do an strace to see where /dev/mem is being used. If you are using multiple nodes, hydra only relies on passwordless ssh. It doesn't really care what the user id is (root or non-root). -- Pavan On 06/13/2013 09:27 AM, Lee, Eibhlin wrote:
Unfortunately I didn't come across this mailing list until recently. Sods law. ./main does not work but sudo ./main does work. Could hydra compile and run a program where this is the case? I ask because the only way I'll be able to get around using sudo is to change ownership of /dev/mem. It goes without saying that that's dangerous! Eibhlin ________________________________________ From: Pavan Balaji [[email protected]] Sent: 13 June 2013 15:21 To: [email protected] Cc: Lee, Eibhlin Subject: Re: [mpich-discuss] Running an mpi program that needs to access /dev/mem
smpd was mainly meant for windows support. It is now deprecated, so we don't officially support that. Someone on the mailing list might help, but no promises.
With respect to hydra, problems with that is what you should have reported on this mailing list and we would have tried to help. :-)
If ./main itself is not working, there's no hope of getting it to work with mpiexec. You'll need to debug that first.
-- Pavan
On 06/13/2013 09:09 AM, Lee, Eibhlin wrote:
Pavan, I had a lot of trouble getting hydra to work without having to enter a password/passphrase. I saw the option to pass a phrase in the mpich installers guide. I eventually found that for that command you needed to use the smpd process manager. That's the only reason I chose smpd over hydra. As to your other suggestion. I ran ./main and the same error (Can't open /dev/mem...) appeared. sudo ./main works but of course without multiple processes. Eibhlin ________________________________________ From: [email protected] [[email protected]] on behalf of Pavan Balaji [[email protected]] Sent: 13 June 2013 14:34 To: [email protected] Subject: Re: [mpich-discuss] Running an mpi program that needs to access /dev/mem
I just saw your older email. Why are you using smpd instead of the default process manager (hydra)?
-- Pavan
On 06/13/2013 08:05 AM, Pavan Balaji wrote:
What's "-phrase"? That's not a recognized option. I'm not sure where the /dev/mem check is coming from. Try running ~/main without mpiexec first.
-- Pavan
On 06/13/2013 06:56 AM, Lee, Eibhlin wrote:
Hello all,
I am trying to use two raspberry-pi to sample and then process some data. The first process samples while the second processes and vice versa. To do this I use gpio and also mpich-3.0.4 with the process manager smpd. I have successfully run cpi on both machines (from the master machine). I have also managed to run a similar program but without the MPI, this involved compiling with gcc and when running putting sudo in front of the binary file.
When I combine these two processes I get various error messages. For input: mpiexec -phrase cat -machinefile machinefile -n 2 ~/main the error is: Can't open /dev/mem Did you forget to use 'sudo .. ?'
For input: sudo mpiexec -phrase cat -machinefile machinefile -n 2 ~/main the error is: sudo: mpiexec: Command not found
I therefore put mpiexec into /usr/bin
now for input: sudo mpiexec -phrase cat -machinefile machinefile -n 2 ~/main the error is: Can't open /dev/mem Did you forget to use 'sudo .. ?'
Does anyone know how I can work around this? Thanks, Eibhlin
_______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss
-- Pavan Balaji http://www.mcs.anl.gov/~balaji _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss
-- Pavan Balaji http://www.mcs.anl.gov/~balaji
-- Pavan Balaji http://www.mcs.anl.gov/~balaji