On Wed, Jun 24, 2020 at 11:20:55PM +0200, Peter Zijlstra wrote: > On Wed, Jun 24, 2020 at 01:31:44PM -0700, Sami Tolvanen wrote: > > This change limits function inlining across translation unit > > boundaries in order to reduce the binary size with LTO. > > > > The -import-instr-limit flag defines a size limit, as the number > > of LLVM IR instructions, for importing functions from other TUs. > > The default value is 100, and decreasing it to 5 reduces the size > > of a stripped arm64 defconfig vmlinux by 11%. > > Is that also the right number for x86? What about the effect on > performance? What did 6 do? or 4? This is the size limit we decided on for Android after testing on arm64, but the number is obviously a compromise between code size and performance. I'd be happy to benchmark this further once other concerns have been resolved. Sami