Escali 4.4 manual Example, Features

Models: 4.4

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0:MPI_Bcast root: 0 Id: 0 my_count = 32768

0:MPI_Scatter Id: 1

1:MPI_Init

1:MPI_Comm_rank Rank: 1

1:MPI_Comm_size Size: 2

1:MPI_Bcast root: 0 Id: 0 my_count = 32768

1:MPI_Scatter Id: 1

1:MPI_Reduce Sum root: 0 Id: 2

1:MPI_Bcast root: 0 Id: 3

0:MPI_Reduce Sum root: 0 Id: 2

0:MPI_Bcast root: 0 Id: 3

1:MPI_Gather Id: 4

1:MPI_Keyval_free

0:MPI_Gather Id: 4

0:MPI_Keyval_free

If more information is needed the arguments to SCAMPI_TRACE can be enhanced to request more information. The option “-f arg;timing” requests a list of the arguments given to each MPI call, including message size ( useful information when evaluating interconnect performance).

Example:

%SCAMPI_TRACE="-f arg;timing" mpimon ./kollektive-8 ./uf256-8.pgm -- n1 2

0:+-0.951585 s 951.6ms MPI_Init

0:+0.000104 s 3.2us MPI_Comm_rank Rank: 0

0:+0.000130 s 1.7us MPI_Comm_size Size: 2

0:+0.038491 s 66.3us MPI_Bcast root: 0 sz: 1 x 4 = 4 Id: 0 my_count = 32768

0:+0.038634 s 390.0us MPI_Scatter Id: 1

1: +-1.011783 s

1.0s MPI_Init

1:+0.000100 s 3.8us MPI_Comm_rank Rank: 1

1:+0.000129 s 1.7us MPI_Comm_size Size: 2

1:+0.000157 s 69.6us MPI_Bcast root: 0 sz: 1 x 4 = 4 Id: 0 my_count = 32768

1:+0.000300 s 118.7us MPI_Scatter Id: 1

0:+0.039267 s 38.8ms MPI_Reduce Sum root: 0 sz: 1 x 4 = 4 Id: 2

0:+0.078089 s 18.8us MPI_Bcast root: 0 sz: 1 x 8 = 8 Id: 3

1:+0.000641 s 56.2us MPI_Reduce Sum root: 0 sz: 1 x 4 = 4 Id: 2

1:+0.000726 s 113.6us MPI_Bcast root: 0 sz: 1 x 8 = 8 Id: 3

1:+0.002547 s 99.0us MPI_Gather Id: 4

0:+0.079834 s 579.5us MPI_Gather Id: 4

1:+0.002758 s 26.4us MPI_Keyval_free

0:+0.113244 s 1.4us MPI_Keyval_free

There are a number of parameters for selecting only a subset, either by limiting the number of calls and intervals as described above under ‘Timing’ , or selecting or excluding just some MPI calls.

4.2.2 Features

The "-b" option is useful when trying to pinpoint which MPI-call has been started but not completed (i.e. are deadlocked). The "-s/-S/-c/-C"-optionsalso offer useful support for an application that runs well for a longer period and then stop, or for examining some part of the execution of the application.

Scali MPI Connect Release 4.4 Users Guide

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Page 52
Image 52
Escali 4.4 manual Example, Features