On Fri, 8 Aug 2025 22:11:32 GMT, Francesco Andreuzzi <d...@openjdk.org> 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 two > additional commits since the last revision: > > - magic number: 400 > - inline | Feature | Baseline `precompiled.hpp` (Mean ±) | Updated `precompiled.hpp` (Mean ±) | |-----------------------|---------------------|----------------------| | epsilongc | 505.78 ± 9.08 | 499.36 ± 3.21 | | epsilongc cds | 523.93 ± 9.42 | 510.68 ± 0.99 | | epsilongc compiler1 | 514.89 ± 2.28 | 518.67 ± 14.22 | | epsilongc compiler2 | 758.34 ± 5.56 | 736.65 ± 32.95 | | g1gc | 674.96 ± 6.37 | 693.39 ± 23.25 | | epsilongc services jfr| 707.45 ± 2.08 | 670.55 ± 1.50 | | epsilongc jni-check | 522.61 ± 1.82 | 517.46 ± 1.67 | | epsilongc compiler1 jvmci | 604.92 ± 4.23 | 600.61 ± 8.79 | | epsilongc compiler2 jvmci | 836.85 ± 7.40 | 792.07 ± 16.18 | | epsilongc services jvmti | 549.48 ± 6.87 | 553.74 ± 7.67 | | epsilongc management | 486.56 ± 5.68 | 480.58 ± 4.59 | | epsilongc opt-size | 476.57 ± 1.87 | 476.71 ± 1.23 | | parallelgc | 497.28 ± 3.90 | 493.68 ± 2.19 | | serialgc | 477.84 ± 0.86 | 476.14 ± 1.32 | | epsilongc services | 476.99 ± 2.44 | 478.74 ± 3.47 | | shenandoahgc | 676.10 ± 5.35 | 623.43 ± 3.11 | | zgc | 620.95 ± 1.84 | 621.86 ± 4.35 | `±`: maximum and minimum measurements ------------- PR Comment: https://git.openjdk.org/jdk/pull/26681#issuecomment-3176968277
