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Subject: [OMPI users] eager limits?
From: Brock Palen (brockp_at_[hidden])
Date: 2008-03-03 15:18:32


I was writing a simple code to demonstrate deadlock. I create an
array of some number of doubles, when sizeof(double)*SIZE is >
btl_sm_eager_limit (on a smp machine) I expect the code to deadlock
but not until the buffer size is greater than the eager limit.

Now in 1.2.3 sm_eager_limit is 4096 (bytes?) So i expect a buffer of
doubles created with malloc to have up to 512 before the code
deadlocks. (remember this is for demonstrations only) The code
deadlocks at 504 doubles, does the eager limit not include the
envelope overhead? Is it really 64 Kbytes?

Thus does every message take up 64K no matter the size of buffer* ?

Brock Palen
Center for Advanced Computing
brockp_at_[hidden]
(734)936-1985