Uploaded image for project: 'JDK'
  1. JDK
  2. JDK-8240873

Shenandoah: Short-cut arraycopy barriers

    XMLWordPrintable

Details

    • gc
    • b15
    • generic
    • generic

    Backports

      Description

        The strong invariant gives us an opportunity to short-cut arraycopy-barriers:

        - if the src object is beyond the safe-iteration limit, e.g. has been allocated since evac-start, then it can not have any from-space references and thus does not require updating.
        - likewise, if the dst object is beyond TAMS, e.g. has been allocated since mark-start, then it can only have references that must have been reachable otherwise and thus don't require enqueueing in SATB.

        Short-cutting on those condition cuts out 80-90% of arraycopy slowpaths.

        Attachments

          Issue Links

            Activity

              People

                rkennke Roman Kennke
                rkennke Roman Kennke
                Votes:
                0 Vote for this issue
                Watchers:
                2 Start watching this issue

                Dates

                  Created:
                  Updated:
                  Resolved: