From: Michael Somervell <somervell@esv1.auckland.ac.nz>
Newsgroups: comp.parallel.mpi
Subject: MPI as root on SGI PowerChallenge
Date: Fri, 21 Aug 1998 15:13:58 +1200
Organization: University of Auckland, Dept of Engineering Science
Message-Id: <35DCE5F6.B563DD17@esv1.auckland.ac.nz>
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I'm a masters student whose time to finish his thesis is rapidly drawing
to a close and I really need some help. To time my algorithms
accurately, I need to have exclusive access to multiple processors, and
the only way to do this is to have root access. All seems fine and good
until I actually try and run my programs using mpirun ("mpirun -np 8
synchronous") when logged in as root (and no, I am not the
administrator, but he has kindly allowed me to run my algorithms as
root.) The error "MPI: could not run executable" appears every time, so
I look up in the mpirun man page and it says that this could basically
be anything and everything going wrong (note that I do NOT get any
errors logged in as myself and have been happily using it for about a
year.) So we (the admin and I have spent almost an entire day just
trying to figure this one out) mess round with some things, and it just
seems that you plain old cant run mpi when you're root (I tried "su"
when I had logged in as myself so all the environment variables should
still be the same.) Can anyone offer any help at all?

(Its running on a 16 SMP R10000 processor SGI powerchallenge running
IRIX 6.2 btw.)

Thanks