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“K16304” — 2012/11/19 — 9:15
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High Performance Computing Using Commodity Hardware and Software
idle times as great as 60% with the idlest occurring during sends of large messages.
The one-to-many SCTP BTL as well as the TCP BTL used 100% of the CPU, on
both the send and receive side, regardless of whether we were using one link or two.
Results
The following graphs show the OSU Bandwidth results for all the scenarios tested.
We tested varying the BTL design (SCTP one-to-one, SCTP one-to-many, TCP), the
number of network links to use, as well as the MTU. All tests were run with the same
(500000 byte) socket buffer size.
Figure 6.3 Open MPI single-link ...