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From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2007-06-22 16:52:45


On Jun 20, 2007, at 8:29 AM, Jeff Squyres wrote:

> 1. btl_*_min_send_size is used to decide when to stop striping a
> message across multiple BTL's. Is there a reason that we don't
> just use eager_limit for this value? It seems weird to say "this
> message is short enough to go across 1 BTL, even though it'll take
> multiple sends if min_send_size > eager_limit". If no one has any
> objections, we suggest eliminating this MCA parameter (!!) and
> corresponding value and just using the BTL's eager limit for this
> value (this value is set by every BTL, but only used in exactly 1
> place in OB1).
>
> Len: please put this on the agenda for next Tuesday (just so that
> there's a deadline to ensure progress).

No one has commented on this, so I assume we'll discuss on Tuesday. :-)

> 2. rdma_pipeline_offset is bad name; it is not an accurate
> description of what this value represents. See the attached figure
> for what this value is: it is the length that is sent/received
> after the eager match before the RDMA (it happens to be at the end
> of the message, but that's irrelevant). Specifically: it is a
> length, not an offset. We should change this name. Here's some
> suggestions we came up with:
>
> rdma_pipeline_send_length (this is our favorite)

Gleb made this change in the code. I've attached a new slide showing
the new name.

-- 
Jeff Squyres
Cisco Systems