Hi, thanks for your review. On Mon, 2018-10-22 at 21:49 -0400, Kim Barrett wrote:
On Oct 22, 2018, at 9:02 AM, Thomas Schatzl < thomas.schatzl@oracle.com> wrote:
CR: https://bugs.openjdk.java.net/browse/JDK-8212753 Webrev: http://cr.openjdk.java.net/~tschatzl/8212753/webrev/ Testing: hs-tier1-3
Thanks, Thomas
There’s an additional change to the G1 code here: src/hotspot/share/gc/g1/g1ParScanThreadState.cpp 313 } else if (!obj->is_typeArray()) {
which seems unrelated to the described change and unmentioned in the RFR. Is this change intentional here?
No.
Is this a measurable optimization?
On parallel GC and jbb2005 (and probably some specjvm2008 applications as I believe this is the class of applications parallel has been optimized for), it seems to decrease pause time measurably slightly (did some ad-hoc testing right now). For G1 the situation is more fuzzy, as its pause time readings are much more noisy. The change for G1 is very old now, lying around for maybe years, so it slipped in when cutting up some recent improvements.Sorry, wasn't intentional.
For the CMS-conditionalized asserts in forward_to_atomic, please add a comment that CMS may CAS in a special pseudo-oop value.
Done. http://cr.openjdk.java.net/~tschatzl/8212753/webrev.0_to_1 (diff) http://cr.openjdk.java.net/~tschatzl/8212753/webrev.1/ (full) Thanks, Thomas