[Discuss] backport - parallel heap inspection for different GC Heap

[linzang(臧琳)]

Dear All,
     Recently I have made an enhancement that inspect heap parallelly for different GC heap (PSS, G1, Shenandoah and Z) and the patches have been pushed to jdk master. The result show significant speedup of “jmap -histo”.
     I am planing to backport them to jdk14u and jdk11u, and also add CMS Support if needed, but I want to know whether it will be accept before starting the real work, because it add “parallel” option to jmap command, which may affect compatibility.
     May I ask your opinion about it? Thanks.

     FYI. The original bug: https://bugs.openjdk.java.net/browse/JDK-8214535

BRs,
Lin