On Wed, 27 Aug 2025 18:06:30 GMT, Francesco Andreuzzi <[email protected]> wrote:
>> In this PR I propose to refresh the included headers in hotspot >> `precompiled.hpp`. The current set of precompiled headers was refreshed in >> 2018, 7 years ago. I repeated the same operations and measurements after >> refreshing the set of precompiled headers according to the current usage >> frequency. >> >> These are the results I observed. Depending on the platform, the improvement >> is between 10 and 20% in terms of total work (user+sys). The results are in >> seconds. >> >> >> linux-x64 GCC >> master real 81.39 user 3352.15 sys 287.49 >> JDK-8365053 real 81.94 user 3030.24 sys 295.82 >> >> linux-x64 Clang >> master real 43.44 user 2082.93 sys 130.70 >> JDK-8365053 real 38.44 user 1723.80 sys 117.68 >> >> linux-aarch64 GCC >> master real 1188.08 user 2015.22 sys 175.53 >> JDK-8365053 real 1019.85 user 1667.45 sys 171.86 >> >> linux-aarch64 clang >> master real 981.77 user 1645.05 sys 118.60 >> JDK-8365053 real 791.96 user 1262.92 sys 101.50 > > Francesco Andreuzzi has updated the pull request incrementally with one > additional commit since the last revision: > > fix absolute path Marked as reviewed by shade (Reviewer). I re-ran the script locally on my Mac, and I think it works without hitches now. There seems to be a tiny bit of variability for generated `precompiled.hpp`, since timing measurements are not exactly precise or consistent across build platforms. But IMO it is not worth diving deeper into. The build times are still improving, as I tested earlier. So, great work all around here, folks. Kudos Francesco for trying multiple approaches and working out the great one! I think we are good to go. If we need any other changes, we can do them as follow-ups. ------------- PR Review: https://git.openjdk.org/jdk/pull/26681#pullrequestreview-3164025632 PR Comment: https://git.openjdk.org/jdk/pull/26681#issuecomment-3232687434
