On Fri, 17 Apr 2026 13:09:29 GMT, Frederic Parain <[email protected]> wrote:
> The addition of the NULLABLE_NON_ATOMIC_FLAT layout forced the addition of a > null-marker in all value classes instances, causing a instance size increase > for value classes which didn't supported any nullable layout before. This > size increase caused some performance regressions which boxing classes Double > and Long. This patch temporarily disables the support for the > NULLABLE_NON_ATOMIC_FLAT layout in classes Long and Double. A longer term > solution will be developed and is tracked by JDK-8382361. > > Tested on Mach5: tiers 1-4 > Thanks to @dafedafe for measuring the performance with the fix. > > - [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: 7cb66d66 Author: Frederic Parain <[email protected]> URL: https://git.openjdk.org/valhalla/commit/7cb66d664c917876b22e264dbf66ef5f0f16cf51 Stats: 7 lines in 1 file changed: 6 ins; 0 del; 1 mod 8379145: [lworld] Boxing performance regression Reviewed-by: chagedorn, dfenacci ------------- PR: https://git.openjdk.org/valhalla/pull/2331
