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Subject: Re: [OMPI users] running as rank 0 of 1 for 2 processor
From: Raymond Wan (rwan_at_[hidden])
Date: 2009-02-13 03:17:12

Hi Ramya,

Ramya Narasimhan wrote:
> Hi,
> I have installed openmpi-1.3. When I checked for the example programs,
> the output shows only rank 0 of size 1 for 2 processors. When I gave the
> command: *mpirun -hostfile node -np 2 hello_c*
> the output is
> Hello, world, I am 0 of 1
> Hello, world, I am 0 of 1
> In my node file, I have
> *IP address* slots=2 max_slots=2
> I don't know why it is not giving as 0 of 2 and 1 of 2.

Other than the text output, can you confirm that this is happening? I'm no expert, but as a sanity check, I would put an infinite loop after printing "hello, world". Then opening another terminal and run "top". I'm not sure if all top's are the same, but I would hit "f" to include more fields and then "J" to include the "Last used cpu". Check the help manual for your top if its different for you. On my top, this information is not included by default. Then return to the previous screen.

Ideally, you should see two processes running on your computer. One on processor "0" and the other on "1". Can you confirm this is not the case and both are set to "0"?