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= GNU Parallel =
GNU parallel is a shell tool for executing many small independent tasks on the multi-core platform (compute nodes). A job can be a single command or a small script that has to be run for each of the lines in the input. GNU parallel can then split the input and pipe it into commands in parallel.

== Adding GNU Parallel to Environment ==
To use GNU parallel on the command line,

{{{#!bash
module load parallel
}}}

== GNU Parallel Syntax ==
* Reading commands to be run in parallel from an input file
{{{
  parallel [OPTIONS] < CMDFILE
}}}
* Reading command arguments on the command line
{{{
  parallel [OPTIONS] COMMAND [ARGUMENTS] ::: ARGLIST
}}}
* Reading command arguments from an input file
{{{
  parallel [OPTIONS] COMMAND [ARGUMENTS] :::: ARGFILE
}}}


[https://www.gnu.org/software/parallel/parallel_tutorial.html]

== Many Task Computing ==
For example, you have many scripts to run,
{{{
[fuji@cypress1 JobArray2]$ ls
hello2.py    script01.sh  script03.sh  script05.sh  script07.sh  script09.sh   slurmscript2
script00.sh  script02.sh  script04.sh  script06.sh  script08.sh  slurmscript1
}}}

To run all distributed over 4 cores,
{{{
[fuji@cypress1 JobArray2]$ parallel -j 4 sh ::: script??.sh
}}}