$ cabal bench --benchmark-options="+RTS -N8"
Replace 8 with how many physical threads you want to use.
This program makes use of the cabal-install build tool (the command
line program is just called cabal). You will need at least cabal
3.0.0.0.
There are two programs here: ray, which is used for generating
images, and bench-ray, which is a benchmarking harness that makes
use of the excellent criterion library. First you must run the
following command:
cabal update
Then you can build both by running
cabal build --enable-benchmarks
For running the programs, use cabal run. For example, to generate
a 400x400 image of the "rgbbox" scene as rgbbox.png:
cabal run -v0 ray -- rgbbox 400 400
For running the benchmarks:
cabal run -v0 bench-ray --
You can also specify only a subset of benchmarks to run; for example to run only the BVH calculation benchmarks:
cabal run -v0 bench-ray bvh --
To run with multiple threads, place +RTS -Nx at the end of the
command line, where x is the number of threads to use, e.g:
cabal run -v0 bench-ray bvh -- +RTS -N4
It is crucial that the RTS options go after --, as otherwise
they will be consumed by the cabal executable itself.