On Tue, 12 Dec 2023 22:18:33 GMT, Alex Menkov <amen...@openjdk.org> wrote:
> I.e. merge is performed on main java thread, but VM is at safepoint So is the main thread operating in_native whilst doing the merge? I suspect the admonition of not doing the merge at a safepoint actually meant "not a safepoint by the VMThread" as that would cause the whole VM to pause. Even doing it in the VMThread at all can delay the next safepoint, which does not seem good. I'm not familiar with this code in general (and only looked at this because of the previous issue in the CI) but I'm unclear what including virtual thread stack referencves has to do with the merging logic? I would not expect merging to be affected by the current change. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/17040#discussion_r1424670985