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From: Brock Palen (brockp_at_[hidden])
Date: 2007-06-11 11:27:03


With openmpi-1.2.0

i ran a: ompi_info --param btl tcp

and i see reference to:

MCA btl: parameter "btl_tcp_min_rdma_size" (current value: "131072")
MCA btl: parameter "btl_tcp_max_rdma_size" (current value: "2147483647")

Can TCP support RDMA? I thought you needed fancy hardware to get
such support? Light on this subject is highly appreciated.

  Also if a user using ethernet, is trying to up the limit for
'greedy' messages that the btl_tcp_eager_limit? Is there a problem
increasing its size? We will test it with his app of-course, but
was wondering if there was a 'gotcha' I was going to walk into.
Thanks

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