# 18.1.3. mpisync

mpisync — Open MPI timing tools

## 18.1.3.1. SYNTAX

`mpisync [options]`

`mpirun_prof [options]`

`ompi_timing_post [<timing-file>] [<processed-file>]`

## 18.1.3.2. DESCRIPTION

`mpisync`: determines clock offsets relative to Head Node Process (HNP). It accepts the following options:

- `-o`, `--output`: The name of output file where offsets related to HNP will be written

- `-h`, `--help`: Print help information

`ompi_timing_post` takes the timing output file as input parameter. The events are sorted by the timestamps. Next, the timestamps are replaced with time offsets relative to the `first` : `previous` event.

`mpirun_prof` is a wrapper around mpirun that performs clock synchronisation and post-processing of the timing output file.

## 18.1.3.3. NOTES

The mpisync code was derived from MPIPerf project: http://mpiperf.cpct.sibsutis.ru/index.php/Main/Documentation

## 18.1.3.4. FILES

The output file has following format:

    <hostname> <round-trip-time> <offset-from-hnp>