p. 158, first paragraph: Tom Cormen notes that in systems using Unix, it may be possible to improve performance by insuring that each of the files, file.0, file.1, etc., resides on the same disk as the corresponding process. For example, suppose process 0 is running on machine A with a local disk mounted on /a, process 1 is running on machine B with a local disk mounted on /b, etc. We may be able to symbolically link files on the local drives to file.0, file.1, . . . :
pages 284-293, Section 13.2 on hypercube allgather: Tom also
observed that if the algorithm first exchanges data between
processes with ranks differing only in the least
significant bit and then exchanges data between processes
with ranks differing in successively more significant bits,
the exchanged data will always be contiguous, and it won't
be necessary to use derived types. In addition to simplifying
the code, this would probably result
in a considerable performance improvement. [00/01/29]
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