git-annex/doc/git-annex-benchmark.mdwn

# NAME

git-annex benchmark - benchmark git-annex commands

# SYNOPSIS

git annex benchmark [criterionopts] ( -- commmand [; command] | --databases )

# DESCRIPTION

When git-annex is built with benchmarking support, this command can be used
to benchmark any other git-annex command. For example
"git annex benchmark -- get ."
will benchmark "git annex get".

The command being benchmarked is run in the current git-annex repository.
It does not run just once; the benchmarking process will run it several
times to get a statistically meaningful result.

When benchmarking an action like "git annex get", the first run will
often do much more than subseqent runs. To make the benchmark repeat an
action like getting a file each time, additional commands can be listed,
separated by ';'. (Note that ';' needs to be escaped from the shell.)
The combined script will be run repeatedly by the benchmark. An example
of using this:

	git annex benchmark -- get . ';' drop .

Note that git-annex benchmark does not fork new git-annex processes when
benchmarking; it calls the command to benchmark internally, and so avoids
git-annex's startup overhead. (So don't try to use it to optimise git-annex
startup.) 

# OPTIONS

Before the "--" any of the criterion library's command-line options can be
used.

Any options that git-annex usually accepts can be included after the
command to benchmark.

The --databases option benchmark's git-annex's use of sqlite databases,
instead of a command.

# OUTPUT

The output of the commands being benchmarked goes to standard output and
standard error as usual. It's often a good idea to sink it to /dev/null to
avoid the display of the output skewing the benchmark results. Of course
--quiet can also be used to avoid most git-annex output, as long as you
don't want to benchmark the generation of that output.

The benchmark report is output to standard output by default, although
criterion options can be used to redirect it to a file.

# SEE ALSO

[[git-annex]](1)

# AUTHOR

Joey Hess <id@joeyh.name>

Warning: Automatically converted into a man page by mdwn2man. Edit with care.