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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-08-16 12:23:46


On Aug 16, 2007, at 11:48 AM, Tim Prins wrote:

>> +#define ORTE_RML_TAG_UDAPL 25
>> +#define ORTE_RML_TAG_OPENIB 26
>> +#define ORTE_RML_TAG_MVAPI 27
>>
>> I think that UDAPL, OPENIB, MVAPI should not appear anywhere in the
>> ORTE layer ...
> I tend to agree with you. However, the precedent has been set long ago
> to put all these constants in this file (i.e. there is
> ORTE_RML_TAG_WIREUP and ORTE_RML_TAG_SM_BACK_FILE_CREATED which are
> only
> used in OMPI), and it makes sense to have all tags defined in one
> place.

I think George's point is that the names UDAPL, OPENIB, MVAPI are all
specific to the OMPI layer and refer to specific components. The
generic action WIREUP was probably somewhat forgivable, but
SM_BACK_FILE_CREATED is probably the same kind of abstraction break
as UDAPL/OPENIB/MVAPI, which is your point.

So you're both right. :-) But Tim's falling back on an older (and
unfortunately bad) precedent. It would be nice to not extend that
bad precedent, IMHO...

> If we end up doing the runtime services layer, all the ompi tags would
> be defined in the RSL, and this will become moot.

True. We will need a robust tag reservation system, though, to
guarantee that every process gets the same tag values (e.g., if udapl
is available on some nodes but not others, will that cause openib to
have different values on different nodes? And so on).

-- 
Jeff Squyres
Cisco Systems