Open MPI logo

Open MPI Development Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Development mailing list

Subject: Re: [OMPI devel] [OMPI svn-full] svn:open-mpi r21292
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2009-05-27 20:43:30


I think Ralph was asking "where is this value used?"

This particular value is one of the constants defined in mpi.h, and
it's used in some of the public MPI data structures (the length of
some strings returned by MPI to the application).

On May 27, 2009, at 8:40 PM, George Bosilca wrote:

> No there is no such constraint. Rainer's commit only changed the
> hardcoded value to another define, which this time can be set by the
> user at configure time. However, the default value is exactly the
> same as before (for MPI hostnames is set to 256).
>
> george.
>
> On May 27, 2009, at 20:02 , Ralph Castain wrote:
>
>> I can't find that max hostname constraint in the above commit
>> (probably just tired eyes). However, note that ORTE doesn't have
>> any hostname length constraint, so if we are now adding one to the
>> OMPI layer, we have a problem.
>>
>> For example, in the ompi_proc_t struct, we simply point it at the
>> ORTE name so we avoid impacting the memory footprint by copying the
>> hostname. Thus, it isn't clear to me -where- we are restricting
>> hostname lengths - can someone point it out?
>>
>> FWIQ: we routinely see hostnames much longer than 16 chars on the
>> user list and on many clusters here. Having such a small
>> restriction will cause major problems with our user base.
>>
>>
>>
>> On Wed, May 27, 2009 at 8:11 AM, Jeff Squyres <jsquyres_at_[hidden]>
>> wrote:
>> On May 27, 2009, at 9:54 AM, Rainer Keller wrote:
>>
>> > One thing to note about this change is that it will break binary
>> > compatibility between 1.3/1.4 and the 1.5/1.6 series (since these
>> > values are #define's, and therefore are resolved at compile time --
>> > not run-time).
>> Where's the break??
>>
>>
>> My bad -- you're entirely right. I mis-read; you kept all the
>> defaults exactly the same. Good!
>>
>> Several of my other comments are therefore invalid. :-) But the
>> _OPAL_ -> OPAL_ prefix thing is still relevant (that would be the
>> only _OPAL prefix that I'm aware of).
>>
>> --
>> Jeff Squyres
>> Cisco Systems
>>
>>
>> _______________________________________________
>> devel mailing list
>> devel_at_[hidden]
>> http://www.open-mpi.org/mailman/listinfo.cgi/devel
>>
>> _______________________________________________
>> devel mailing list
>> devel_at_[hidden]
>> http://www.open-mpi.org/mailman/listinfo.cgi/devel
>
> _______________________________________________
> devel mailing list
> devel_at_[hidden]
> http://www.open-mpi.org/mailman/listinfo.cgi/devel

-- 
Jeff Squyres
Cisco Systems