Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8347372

GenShen: clean bitmaps of old gen after coalesce-and-fill

XMLWordPrintable

    • Icon: Enhancement Enhancement
    • Resolution: Unresolved
    • Icon: P4 P4
    • None
    • 25
    • hotspot
    • gc

      Follow up on comment/suggestions of the PR for https://bugs.openjdk.org/browse/JDK-8338737


      https://github.com/openjdk/jdk/pull/22778/files/f82fdfaafe1af5f378bde2be84a0e38d1e17d64e#r1907845214

      ```
      It seems we ought to clear the old-gen mark bitmap at the end of coalesce-and-fill. But that does not allow us to avoid clearing old-gen mark bitmaps at start of bootstrap because when young-gen regions are promoted in place, the mark bitmap is preserved for those regions, and since they are considered old at the end of the GC cycle during which they were promoted, those bitmaps will not be cleared by op_reset_after_collect(). Is there a way to improve this behavior?

      For example, in op_reset_after_collect(), maybe we should clear old-gen bitmaps also (at least for recently promoted in place regions) unless old marking is in process and/or mixed evacuations are in progress.
      ```

            xpeng Xiaolong Peng
            xpeng Xiaolong Peng
            Votes:
            0 Vote for this issue
            Watchers:
            1 Start watching this issue

              Created:
              Updated: