TGQR 2010Q4 Report.pdf - Teragridforum.org

The team also mentioned that they had trouble verifying the result of broadcast. An example
verification procedure using extra I/O was added and was shown to the team. Instructions of
using performance tools to collect performance data and conduct analyses for their code were also
given to the team.
While the solution of this performance is not complex, the team does not seem to have
experience of optimization; thus many instructions were prepared and were given to the team,
include: 1). A set of example programs (base on their code structure) to modify their code step by
step. 2). A power point file with more than 10 slides showing how the problem was solved, step
by step. 3). Performance data, and instruction of how those performance data were
collected/generated.
Figure 5.4 Performance comparison of repeated send/recv and single MPI_Bcast – time in secs
(Y axis) Vs # of cores (X axis) (Plot by Meng-Shiou Wu, NICS)
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