On Fri, 7 Aug 2026 14:14:32 GMT, Fredrik Bredberg <[email protected]> wrote:
> The main objectives for this PR are: > 1) Compact Object Headers needs the Object Monitor Table to work. > 2) Both Compact Object Headers > ([JDK-8360700](https://bugs.openjdk.org/browse/JDK-8360700)) and Object > Monitor Table ([JDK-8379782](https://bugs.openjdk.org/browse/JDK-8379782)) > are now enabled by default. > 3) If we always use the Object Monitor Table, we will free up lots of bits > in the markword, that could be of use to others (read GC). > 4) If we don't need to maintain any "monitor pointer in the mark word" code, > we will simplify the code base. > > Therefore this PR will remove the `UseObjectMonitorTable` flag and related > code. > > Note that this PR only removes the most obvious use of the > `UseObjectMonitorTable` in the code base. This is to ease the burden on the > reviewers. [JDK-8389938](https://bugs.openjdk.org/browse/JDK-8389938) has > been created to finalize the work by removing the less obvious code, like no > longer used mark word code in different GCs. > > The code has passed tier1-7 testing on supported platforms and smoke testing > using QEMU on `RISC-V`, `PowerPC` and `s390`. > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai). This pull request has now been integrated. Changeset: 34dda4ec Author: Fredrik Bredberg <[email protected]> URL: https://git.openjdk.org/jdk/commit/34dda4ecd89e07d4530f9c26e88f9968788d695f Stats: 1034 lines in 34 files changed: 14 ins; 686 del; 334 mod 8389325: Remove the UseObjectMonitorTable flag and related code Reviewed-by: stefank, coleenp ------------- PR: https://git.openjdk.org/jdk/pull/32257
