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Subject: [OMPI devel] sm BTL question: frag alloc
From: Eugene Loh (Eugene.Loh_at_[hidden])
Date: 2009-02-17 20:14:01

(Rich:  same question as I asked you in private e-mail.)

Should the first fragment of a message be an eager fragment even when the message is long and a rendezvous protocol is employed?

So far as I can tell, a long MPI_Send starts like this:

Here we see (e.g., line 368) that if we're over the eager limit, we try to send the first fragment with "eager" size.  Then,


But if we look at it appears to alloc a "MAX" (not EAGER) fragment.  Is this a "bug"?  Should the BTL be allocating an EAGER fragment instead?  Or, could this function possibly be called with size>eager?  Or, should the BTL alloc a MAX *or* EAGER fragment depending on what size is requested?