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Jumpshot is a graphical tool for understanding the performance of parallel
programs. It is in the tradition of the upshot tool, but contains a number of
extensions and enhancements that make it suitable for large-scale parallel
computations. Jumpshot takes as input a new, more flexible logfile format,
and comes with a library for generating such logfiles. An MPI profiling
library is also included, enabling the automatic generation of such logfiles
from MPI programs. Jumpshot is written in Java, and can easily be integrated
as an applet into browser-based computing environments. The most novel feature
of Jumpshot is its automatic detection of anomalous durations, drawing the
user's attention to problem areas in a parallel execution. This capability is
particularly useful in large-scale parallel computations containing very many
events.