Open MPI logo

Open MPI User's Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Open MPI User's mailing list

Subject: [OMPI users] Non-continous ranks with "--np 4 -npernode 3 -bynode"
From: Andrew Senin (andrew.senin_at_[hidden])
Date: 2011-10-04 07:55:53

Hi all,

I noticed a strange behaviour in 1.5.4 which seems to me as a bug. I'm
trying to launch 4 ranks on 2 nodes. If I add "-npernode 3 -bynode"
parameters mpirun freezes on start. When I tried with the "-display-map"
parameter it shows the following:
./mpirun --np 4 --host mir1,mir2 -npernode 3 -display-map -bynode ./hello

 ======================== JOB MAP ========================

 Data for node: mir1 Num procs: 3
        Process OMPI jobid: [42759,1] Process rank: 0
        Process OMPI jobid: [42759,1] Process rank: 2
        Process OMPI jobid: [42759,1] *Process rank: 4*

 Data for node: mir2 Num procs: 1
        Process OMPI jobid: [42759,1] Process rank: 1

Which seems as a problem since there supposed to be no rank #4 as np=4.

I've also tried with trunk. The application also freezes but does not show
the map of ranks.

Could you please assist if this is a bug or I'm doing something improperly?

Andrew Senin