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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-06-13 11:50:07


On Jun 13, 2007, at 11:32 AM, George Bosilca wrote:

> Right ... blame me :) The problem is that we have to know the
> number of
> interfaces in order to be able to generate the MCA parameters, and the
> number of interfaces will only be know inside the init call (and I
> really
> doon't think it's a good idea to move this part of the code in the
> open
> function).

Understood and agree.

> I don't mind having some MCA parameters that are never showed by
> ompi_info
> (we already have the hidden ones). Anyway, for TCP by default there
> is the
> btl_tcp_latency and btl_tcp_bandwidth which will be used as a default
> value for all NICs. For the others, a quick google search on our
> mailing
> list will return all information about how to set the latency and
> bandwidth by NIC. MX have a similar mechanism ...

Are you saying that the TCP and MX BTLs have similar variable MCA
parameters?

I think the "hidden" MCA parameters are a different issue; they were
created for a different purpose (users are not supposed to see/set
them). These variable parameters would be intended to be used by the
users, but they would have no way of finding out a) that they exist,
and b) what they are. That's why I think that the MCA parameters may
not be the right mechanism for this kind of information.

-- 
Jeff Squyres
Cisco Systems