On 11 Jan 2010, at 06:20, Jed Brown wrote: > On Sun, 10 Jan 2010 19:29:18 +0000, Ashley Pittman <ash...@pittman.co.uk> > wrote: >> It'll show you parallel stack traces but won't let you single step for >> example. > > Two lightweight options if you want stepping, breakpoints, watchpoints, > etc. > > * Use serial debuggers on some interesting processes, for example with > > mpiexec -n 1 xterm -e gdb --args ./trouble args : -n 2 ./trouble args : -n > 1 xterm -e gdb --args ./trouble args > > to put an xterm on rank 0 and 3 of a four process job (there are lots > of other ways to get here).
You can also achieve something similar with padb by starting the job normally and then using padb to launch xterms in a similar manner although it's been pointed out to me that this only works with one process per node right now. > * MPICH2 has a poor-man's parallel debugger, mpiexec.mpd -gdb allows you > to send the same gdb commands to each process and collate the output. True, I'd forgotten about that, the MPICH2 people are moving away from mpd though so I don't know how much longer that will be an option. Ashley,
