[
Date Prev][
Date Next][
Thread Prev][
Thread Next][
Date Index][
Thread Index]
[
List Home]
|
Re: [ptp-user] help about PTP SDM
|
Hi Kobol,
The SDM assumes that it will be launched using an MPI runtime. Most, if not all, runtimes use an environment variable to pass the MPI rank, so each SDM process will have a unique rank variable in it's environment when it starts. The SDM process then starts gdb which will pass the environment to the process it is debugging, so ultimately each target process will also have a copy of the unique rank variable in it's environment. The environment variables used by each supported runtime are listed in src/impl/sdm_routing_table_file.c.
Best regards,
Greg
On Nov 30, 2011, at 4:02 AM, june kobol wrote:
> Hi all,
> I saw the source code of SDM, and was confused by the code that MPI processes were spawned by GDB using command "gdb -i mi -tty name -q prog". The function MISessionStartLocal in the file "MISession.c" gives the detailed implementation. In this situation , the ranks of all MPI processes would be zero, isn't it?
> To my knowledge, all MPI tasks should be spawned by resource managers such as SURM, PBS, mpiexec. Then every MPI task can have a unique rank and do collective communication with eath other. If MPI tasks were spawned by GDB, every process would be isolated because all their ranks were zero.
> Is it correct that the launch mode of SDM spawns the MPI task using GDB?
>
> Excepting your reply.
>
>
> Regards,
>
> kobol
>
>
> _______________________________________________
> ptp-user mailing list
> ptp-user@xxxxxxxxxxx
> https://dev.eclipse.org/mailman/listinfo/ptp-user
