Doonv d7c65e40ee Use -Z threads=0 option in config_fast_builds.toml (#11541) ... # Objective Improve compile times. ## Solution The `-Z threads=0` option has been introduced into nightly rust somewhat recently, and was showcased in this [rust-lang article](https://blog.rust-lang.org/2023/11/09/parallel-rustc.html). This option improves multithreading in rust and speeds up compilation. I added this option to `config_fast_builds.toml` so others can also use this option to improve compile times. `-Z threads=0` automatically uses the same amount of threads as the amount of threads in your system (See [rustc source code](6b4f1c5e78/compiler/rustc_session/src/options.rs (L617))). ### Benchmarks > **Disclaimer:** This section was written before I knew of `-Z threads=0`, so it uses `-Z threads=8` instead. I compiled bevy with/without the `-Z threads=8` and saw about a 7% improvement in compliation times on my Kubuntu system with a 13th Gen Intel® Core™ i5-13400. Also the compile times go down over time, probably because I had other things running in the background. #### Without `-Z threads=8` - 42.33s - 40.90s - 38.27s - 38.07s - 37.17s - 37.67s - 36.63s - 37.24s **Average**: 38.535 #### With `-Z threads=8` - 36.77s - 39.50s - 38.86s - 35.61s - 34.37s - 34.32s - 34.44s - 33.74s **Average**: 35.95125		2024-01-29 23:13:22 +00:00
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config_fast_builds.toml	Use -Z threads=0 option in config_fast_builds.toml (#11541)	2024-01-29 23:13:22 +00:00