JDK-8365053 : Refresh hotspot precompiled.hpp with headers based on current frequency
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: runtime
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2025-08-07
  • Updated: 2025-08-28
  • Resolved: 2025-08-28
The Version table provides details related to the release that this issue/RFE will be addressed.

Unresolved : Release in which this issue/RFE will be addressed.
Resolved: Release in which this issue/RFE has been resolved.
Fixed : Release in which this issue/RFE has been fixed. The release containing this fix may be available for download as an Early Access Release or a General Availability Release.

To download the current JDK release, click here.
JDK 26
26 masterFixed
Related Reports
Relates :  
JDK-8366111 - Look into Clang -ftime-trace output
Relates :  
JDK-8365829 - Multiple definitions of static 'phase_names'
Description
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.

I kept the same threshold (130) because none of the other values I tested performed better. However, I noticed including `.inline.hpp` files improved significantly the runtime, thus I propose to include them in all platforms.

These are the results I observed. Depending on the platform, the improvement is between 10 and 18% 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
Comments
Changeset: a5a23400 Branch: master Author: Francesco Andreuzzi <andreuzzi.francesco@gmail.com> Committer: Aleksey Shipilev <shade@openjdk.org> Date: 2025-08-28 09:28:58 +0000 URL: https://git.openjdk.org/jdk/commit/a5a234005414a58f66c7e646a8f9b0042e9f9eec
28-08-2025
Moving from hotspot/other -> hotspot/runtime. I don't believe we use hotspot/other and moving it to hotspot/runtime will get this issue in a triage team's queue.
07-08-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/26681 Date: 2025-08-07 16:47:04 +0000
07-08-2025