Distributed ThinLTO Build Support in Kbuild
summary
Kbuild adds a distributed ThinLTO mode that extracts the LTO index from VMLinux.A and generates backend compile actions and a new makefile so the build system invokes compilers directly; final linking still uses the linker. Distributed builds let individual backends use per-file compiler flags, expose final .o files for tools like kpatch/livepatch and objecttool, and are Google's predominant mode. Build time is roughly the same as in-process ThinLTO when function sections are enabled, but binaries differ due to option handling and function ordering.
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chapters (7)
- 0:00Introduction to ThinLTO
- 2:59Distributed ThinLTO workflow
- 5:48Why distributed ThinLTO
- 7:15Implementation in Kbuild
- 8:40Build performance results
- 11:11Summary and future
- 11:31Q&A session
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