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From: Troy Telford (ttelford.groups_at_[hidden])
Date: 2007-02-13 18:44:57


On Tue, 13 Feb 2007 12:27:07 -0700, Ralph H Castain <rhc_at_[hidden]> wrote:

> Oh, I should have made something clear - I believe those command line
> options aren't available in the 1.1 series. You'll have to upgrade to 1.2
> (available in beta at the moment).
>
>> Actually, that isn't the complete story. Open MPI will automatically
>> run in
>> several ways:
>>
>> 1. one proc in each available slot on every node in your allocation:
>> just
>> don't include -np on your command line. You can rank them by slot
>> (--byslot
>> or leave out) or by node (--bynode).
>>
>> 2. one proc on each node in your allocation: use --pernode on your
>> command
>> line. You can limit the number of nodes used by combining --pernode
>> with -np
>> <foo> - we will launch <foo> procs, one per node
>>
>> 3. a specified number of procs on every node: use --npernode <n>.
>> Again, you
>> can limit the number of procs launched by combining it with -np and can
>> rank
>> by slot or node

This is good to know; for some reason it seemed logical that the batch
scheduler should know how many processes per node, and TM should be able
to get the information. But that's making assumptions...

Thanks!

-- 
Troy Telford