RFR: Reset coalesce and fill boundary during global collect

[Kelvin Nilsen]

On Thu, 14 Oct 2021 22:27:49 GMT, William Kemper <wkemper at openjdk.org> wrote:

> Normally, this happens during cset selection for the old generation. It also needs to happen for coalesce and fill at the end of global collections or objects may not be filled.

My concern is that if we insert code to reset_coalesce_and_fill_boundary() for the entire region before we invoke region->oop_fill_and_coalesce(), then we would need region->oop_fill_and_coalesce() to reregister all the live objects (because we just zapped all of their registrations).

Maybe the "problem" is that we are failing to reset_coalesce_and_fill_boundary() when we begin a stop-the-world or GLOBAL collection.  This would cause the regions outside the cset to not be coalesced and filled.

Oh, that's exactly what you were doing.  So sorry.
I misunderstood which API you were invoking.

Probably means I chose bad names for these services.  :(

-------------

PR: https://git.openjdk.java.net/shenandoah/pull/90