Linux 7.4 merges kernel build speed patches, up to 70% faster incremental builds

The initial batch of kernel build optimization patches by Arm engineer Lorenzo Stoakes has been merged into Linux 7.4. These Kbuild changes address single-threaded bottlenecks and inefficiencies in the build pipeline. When the full patch series is applied, benchmarks showed kernel builds approximately 36% faster and incremental builds roughly 70% faster for both GCC and LLVM/Clang toolchains.

What the Kbuild patches change

• Avoids allocating .modinfo in vmlinux, reducing link-time overhead
• Speeds up kallsyms symbol processing and removes unnecessary sorting steps
• Emits relocations only on the final vmlinux link instead of intermediate stages
• Re-implements mksysmap in C for better performance
• Caches more cc-option and ld-option test results to avoid redundant compiler probes
• Uses pigz (parallel gzip) where available for faster compression

Why it matters

Faster kernel builds benefit distribution maintainers, kernel developers, and CI systems that compile Linux frequently. The improvements apply to both GCC and Clang builds.