8233378: CHT: Fast reset

[walulyai]

Hi all,

Please review this change to add a dedicated method that just resets the internal table (optionally setting it to a new size) without going through new/delete of the CHT. Currently, the CHT destructor calls Value::destroy_node() on every element in the table which may be very slow for some use-cases.

Testing: tier 1-3 (Linux, Windows).

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issue

• JDK-8233378: CHT: Fast reset

Reviewers

• Thomas Schatzl (@tschatzl - Reviewer)
• Robbin Ehn (@robehn - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/3950/head:pull/3950
$ git checkout pull/3950

Update a local copy of the PR:
$ git checkout pull/3950
$ git pull https://git.openjdk.java.net/jdk pull/3950/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 3950

View PR using the GUI difftool:
$ git pr show -t 3950

Using diff file

Download this PR as a diff file:
https://git.openjdk.java.net/jdk/pull/3950.diff

[bridgekeeper]

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[openjdk]

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[mlbridge]

Webrevs

• 00: Full (ff95942e)

[tschatzl]

Lgtm

[walulyai]

Thanks @tschatzl

[openjdk]

@walulyai 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:

8233378: CHT: Fast reset

Reviewed-by: tschatzl, rehn

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 24 new commits pushed to the master branch:

• 9c9c47e: 8266813: Shenandoah: Use shorter instruction sequence for checking if marking in progress
• 0344e75: 8266794: Remove dead code notify_allocation_jvmti_allocation_event
• 9e6e222: 8266892: avoid maybe-uninitialized gcc warnings on linux s390x
• 6575566: 8266787: Potential overflow of pointer arithmetic in G1ArchiveAllocator
• 8468001: 8263452: Javac slow compilation due to algorithmic complexity
• 67cb22a: 8266601: Fix bugs in AddLNode::Ideal transformations
• 18e9d28: 8266676: G1: Remove dead code init_node_id_to_index_map()
• 0e7bdae: 8265062: Remove duplication constant MaxTextureSize
• 10a049e: 8265956: JVM crashes when matching LShiftVB Node
• 9713152: 8262092: vmTestbase/nsk/jvmti/scenarios/hotswap/HS102/hs102t001/TestDescription.java SIGSEGV in memmove_ssse3
• ... and 14 more: https://git.openjdk.java.net/jdk/compare/0f925d1f58ffc0c56ae85a189798f8d99d90d443...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.

[robehn]

Looks ok! Thanks for also adding the gtests.

[walulyai]

Thanks @robehn

[walulyai]

/integrate

[openjdk]

@walulyai Since your change was applied there have been 50 commits pushed to the master branch:

• f3b510b: 8266923: [JVMCI] expose StackOverflow::_stack_overflow_limit to JVMCI
• 548899d: 8266189: Remove C1 "IfInstanceOf" instruction
• b46086d: 8266874: Clean up C1 canonicalizer for TableSwitch/LookupSwitch
• 97367c0: 8266808: Search label still uses old search field id
• 06d7602: 8261158: JVMState should not be shared between SafePointNodes
• 476994a: 8266531: ZAddress::address() should be removed from SA
• e828a93: 8261395: C1 crash "cannot make java calls from the native compiler"
• 3c47cab: 8261034: improve jcmd GC.class_histogram to support parallel
• ed32e02: 8241187: ToolBox::grep should allow for negative filtering
• cc03734: 8266925: Add a test to verify that hidden class's members are not statically invocable
• ... and 40 more: https://git.openjdk.java.net/jdk/compare/0f925d1f58ffc0c56ae85a189798f8d99d90d443...master

Your commit was automatically rebased without conflicts.

Pushed as commit dcf250d.

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