git-annex-benchmark − benchmark git-annex commands
git annex benchmark [criterionopts] ( −− commmand [; command] | −−databases=N )
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.)
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=N option benchmark’s git-annex’s use of sqlite databases, instead of a command. N is the number of items to benchmark.
The output of the commands being benchmarked goes to standard output and standard error as usual. It’s often a good idea to use −−quiet to avoid unnecessary output, unless the generation of that output is part of what you want to benchmark.
The benchmark report is output to standard output by default, although criterion options can be used to redirect it to a file. For example:
git annex benchmark −o bench −− find >/dev/null
Joey Hess <[email protected]>