[11u] RFR/A: 8231209: [REDO] JDK-8207266 ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread

[Hohensee, Paul]

The CSRs have been approved, and the JBS issues tagged (8231209, 8231968 and the corresponding backport issues 8247806 and 8247809). Also, Oracle has now committed to backport these to their 11.0.9. Please approve.

Thanks,
Paul

From: serviceability-dev <serviceability-dev-bounces at openjdk.java.net> on behalf of "Hohensee, Paul" <hohensee at amazon.com>
Date: Thursday, June 18, 2020 at 12:29 PM
To: "jdk-updates-dev at openjdk.java.net" <jdk-updates-dev at openjdk.java.net>
Cc: serviceability-dev <serviceability-dev at openjdk.java.net>
Subject: [11u] RFR/A: 8231209: [REDO] JDK-8207266 ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread

This request is for a pair of backports. 8231209 is the first (and primary), 8231968 is a minor cleanup. There are CSR’s for both. The effect is to add a convenience method getCurrentThreadAllocatedBytes() to com.sun.management.ThreadMXBean that can be implemented more efficiently than the equivalent getThreadAllocatedBytes(long id), and to make the implementation of getThreadAllocatedBytes(long id) and getThreadAllocatedBytes(long[] id) more efficient. These methods are heavily used by heap profiling tools, including Amazon’s, and their efficiency is important to us. There is no effect on the TCK because com.sun.management is a platform-specific package. See the CSRs for more detail.

The patches apply cleanly (in sequence) to 11u, but I’m posting a review/approval request because the backport CSRs need approval. Once the backport CSRs are reviewed, finalized, and approved, l can tag 8231209 and 8231968.

Tested with

hotspot/jtreg/vmTestbase/nsk/monitoring
jdk/com/sun/management
jdk/jdk/jfr/event/runtime

The same tests pass/fail as with unpatched jdk11u-dev.

JDK-8231209: [REDO] JDK-8207266 ThreadMXBean::getThreadAllocatedBytes() can be quicker for self thread

Original RFE: https://bugs.openjdk.java.net/browse/JDK-8231209
Original Patch: https://hg.openjdk.java.net/jdk/jdk/rev/c29e49148be7
Original CSR: https://bugs.openjdk.java.net/browse/JDK-8231374
Original review thread: https://mail.openjdk.java.net/pipermail/serviceability-dev/2019-September/029208.html
Backport RFE: https://bugs.openjdk.java.net/browse/JDK-8247806
Backport CSR: https://bugs.openjdk.java.net/browse/JDK-8247807
JDK-8231968: getCurrentThreadAllocatedBytes default implementation s/b getThreadAllocatedBytes
Original RFE: https://bugs.openjdk.java.net/browse/JDK-8231968
Original Patch: https://hg.openjdk.java.net/jdk/jdk/rev/5bb426e9acc4
Original CSR: https://bugs.openjdk.java.net/browse/JDK-8232072
Original review thread: https://mail.openjdk.java.net/pipermail/serviceability-dev/2019-October/029659.html
Backport RFE: https://bugs.openjdk.java.net/browse/JDK-8247809
Backport CSR: https://bugs.openjdk.java.net/browse/JDK-8247810

Thanks,
Paul