On Wed, 10 Jun 2026 20:26:08 GMT, Chris Plummer <[email protected]> wrote:
> This is a test bug. The gets the first region, gets top() for the that > region, and then uses that top() address to get the region that top() is in. > It expects it to be the same region. However, when the region is full, top() > is actually the next address beyond the end of the region, so marks the start > of the next region. The fix is to simply subtract 1 from top() when it equals > end(). Note top() is where the next allocation comes from in the region and > end() is the end of region space. > > I improved the test by adding printing of the G1 heap, including all regions. > I also improved the test by making it test every region, not just the first > one. During local testing the first region was always free, so did not make > for a very good test, and would not reproduce the issue. When I started > testing every region, it failed every time. All you need is one full region > for failures. > > I ran the test 100 times on all supported platforms. > > --------- > - [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: e965fcf2 Author: Chris Plummer <[email protected]> URL: https://git.openjdk.org/jdk/commit/e965fcf2c08851e443747fe4a47bfb96c15ab748 Stats: 38 lines in 1 file changed: 33 ins; 0 del; 5 mod 8386124: Test serviceability/sa/TestG1HeapRegion.java failed: Address of G1HeapRegion does not match Reviewed-by: kevinw, ysuenaga ------------- PR: https://git.openjdk.org/jdk/pull/31469
