2b9ad2ab33
This is so that the module could be easily imported in e.g. project-config.jam and then used for default build, custom build variants, etc.
Boost.JSON Benchmarks
To run the benchmarks first run clone.sh to fetch the third party repositories. Then run the bench program with no arguments for a list of command line options.
When building with b2, it is possible to create several different copies of the
bench program for different build properties (toolset, build variant, etc.).
Rather than figuring out where those programs are located from b2 output you
can simply run them directly from the build system. For this, use the
bench//run target. For example:
b2 variant=release toolset=gcc,clang bench//run
You can set bench options using the flag bench.option. By default the
target uses all files from the bench/data directory as benchmark data. If you
want to use just a few of those files or use different files altogether, use
the flag bench.file. Finally, when running benchmarks it is often necessary
to use a wrapper program that sets up the process for better result stability.
This can be achieved with the flag bench.launcher. In this case also consider
telling b2 to not run several jobs at a time with -j1, as they would
interfere with each other. Combining everything together we get:
b2 -j1 variant=release toolset=gcc,clang bench//run bench.option=-t:p bench.option=-n:10 bench.option=-i:b bench.launcher="nice -n -20 taskset -c 1" bench.file=mydata.json
Which is the equivalent of
nice -n -20 taskset -c 1 path/to/gcc/version/of/bench -t:p -n:10 -i:b mydata.json
nice -n -20 taskset -c 1 path/to/clang/version/of/bench -t:p -n:10 -i:b mydata.json
Alternatively, you can copy the version of bench that you want into the bench
directory by requesting the target bench//bench-local and then run it
manually:
b2 variant=release toolset=gcc bench//bench-local
nice -n -20 taskset -c 1 bench/bench-local -t:p -n:10 -i:b mydata.json
The benchmarked files were sourced from the simdjson repository.