8319650: Improve heap dump performance with class metadata caching

[shipilev]

Unclean backport to improve heap dump performance. The uncleanliness comes from JDK-8306441 that does not exist in JDK 21, and which I don't think we want to backport at the moment. I had to add a few more ResourceMark-s near HeapDumpWriter to manage the cache allocations.

Additional testing:

• MacOS AArch64 server release, heap dump performance improved
• Linux x86_64 server fastdebug, serviceability/ (contains heap dump tests)
• Linux x86_64 server fastdebug, runtime/ErrorHandling (contains heap dump on failure tests)
• Linux x86_64 server fastdebug, gc/epsilon (contains heap dump on failure tests)
• Linux x86_64 server fastdebug, sun/tools/jhsdb (contains heap dump tests)

---

Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• Change must not contain extraneous whitespace
• JDK-8319650 needs maintainer approval
• Commit message must refer to an issue

Issue

• JDK-8319650: Improve heap dump performance with class metadata caching (Enhancement - P4 - Approved)

Reviewers

• Paul Hohensee (@phohensee - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk21u.git pull/388/head:pull/388
$ git checkout pull/388

Update a local copy of the PR:
$ git checkout pull/388
$ git pull https://git.openjdk.org/jdk21u.git pull/388/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 388

View PR using the GUI difftool:
$ git pr show -t 388

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk21u/pull/388.diff

Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back shade! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

This backport pull request has now been updated with issue from the original commit.

[mlbridge]

Webrevs

• 00: Full (7728d817)

[openjdk]

⚠️ @shipilev This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[shipilev]

/approval request Unclean backport to improve heap dump performance. Tests pass. 21u RFR acked by Paul Hohensee.

[openjdk]

@shipilev
8319650: The approval request has been created successfully.

[openjdk]

@shipilev This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8319650: Improve heap dump performance with class metadata caching

Reviewed-by: phh

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 59 new commits pushed to the master branch:

• f01df29: 8315082: [REDO] Generational ZGC: Tests crash with assert(index == 0 || is_power_of_2(index))
• afc506e: 8319700: [AArch64] C2 compilation fails with "Field too big for insn"
• 3df010f: 8320280: RISC-V: Avoid passing t0 as temp register to MacroAssembler::lightweight_lock/unlock
• ecb199a: 8313616: support loading library members on AIX in os::dll_load
• 220b36c: 8310239: Add missing cross modifying fence in nmethod entry barriers
• d7a3ac7: 8318587: refresh libraries cache on AIX in print_vm_info
• 0941f2c: 8318562: Computational test more than 2x slower when AVX instructions are used
• e7bd0ab: 8319961: JvmtiEnvBase doesn't zero _ext_event_callbacks
• 21a003a: 8320209: VectorMaskGen clobbers rflags on x86_64
• 689b90d: 8318957: enhance agentlib:jdwp help output by info about allow option
• ... and 49 more: https://git.openjdk.org/jdk21u/compare/37888d29125e2ac818600543eb065ea5bf01897e...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[shipilev]

Closing in favor of openjdk/jdk21u-dev#8