Adjust LTO settings - #5408
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Pull request overview
Reduces release build times by relaxing Rust LTO and code-generation settings.
Changes:
- Switches release builds from fat to thin LTO.
- Increases release codegen units to 16.
- Applies profile overrides to unified and non-unified builds.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
Cargo.toml |
Updates workspace release optimization settings. |
src/Makefile.am |
Applies matching Cargo settings across build paths. |
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| codegen-units = 1 | ||
| lto = true | ||
| codegen-units = 16 | ||
| lto="thin" |
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This cuts build times about in half for standard / release / non-fastdev builds. Depending on the machine, it gives up either no measurable runtime perf (on a fast macbook pro) or about 10% of soroswap benchmark median exec time (on a slower older xeon).
Consequently: I'm not certain this is a good idea yet. I think we should do more testing. But I wanted to open a PR to have something to build images off and test on other machines and workloads.