On Mon, 3 Apr 2023 03:32:27 GMT, Ioi Lam <ik...@openjdk.org> wrote: > This PR combines the "open" and "closed" regions of the CDS archive heap into > a single region. This significantly simplifies the implementation, making it > more compatible with non-G1 collectors. There's a net removal of ~1000 lines > in src code and another ~1200 lines of tests. > > **Notes for reviewers:** > - Most of the code changes in CDS are removing the handling of "open" vs > "closed" objects. > - Reviewers can start with ArchiveHeapWriter::copy_source_objs_to_buffer(). > - It might be easier to see the diff with whitespaces off. > - There are two major changes in the G1 code > - The archived objects are now stored in the "old" region (see > g1CollectedHeap.cpp in > [58d720e](https://github.com/openjdk/jdk/pull/13284/commits/58d720e294bb36f21cb88cddde724ed2b9e93770)) > - The majority of the other changes are removal of the "archive" region > type (see heapRegionType.hpp). For ease of review, such code is isolated in > [a852dfb](https://github.com/openjdk/jdk/pull/13284/commits/a852dfbbf5ff56e035399f7cc3704f29e76697f6) > - Testing changes: > - Now the archived java objects can move, along with the "old" regions that > contain them. It's no longer possible to test whether a heap object came from > CDS. As a result, the `WhiteBox.isShared(Object o)` API has been removed. > - Many tests that uses this API are removed. Most of them were written > during early development of CDS archived objects and are no longer relevant. > > **Testing:** > - Mach5 tiers 1 ~ 7
This looks like a nice simplification. Will you also combine all mappings at OS level to a single one, so that you only need one mmap call? ------------- PR Comment: https://git.openjdk.org/jdk/pull/13284#issuecomment-1500812579
