8294847: Fix calculation of G1 effective scanned cards prediction

[tschatzl]

Hi all,

can I have reviews of this change that fixes the prediction of the actually to be scanned cards?

In particular, the current code completely misses the log buffer cards in the "effective" number of scanned cards. The change simply assumes that all pending log buffer cards are going to be scanned, ignoring duplicates.

Other changes are just removing related, unused or unnecessary code.

Depends on PR#10644, so please review that one first.

Testing: gha, local testing, tier1-5 with other changes in this patch series, perf testing with other changes in this patch series

Thanks,
Thomas

---

Progress

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

Issue

• JDK-8294847: Fix calculation of G1 effective scanned cards prediction

Reviewers

• Kim Barrett (@kimbarrett - Reviewer)
• Albert Mingkun Yang (@albertnetymk - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk pull/10647/head:pull/10647
$ git checkout pull/10647

Update a local copy of the PR:
$ git checkout pull/10647
$ git pull https://git.openjdk.org/jdk pull/10647/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 10647

View PR using the GUI difftool:
$ git pr show -t 10647

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/10647.diff

[bridgekeeper]

👋 Welcome back tschatzl! A progress list of the required criteria for merging this PR into pr/10644 will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@tschatzl The following label will be automatically applied to this pull request:

• hotspot-gc

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[mlbridge]

Webrevs

• 03: Full - Incremental (b36bf0fd)
• 02: Full - Incremental (fd1fe4f7)
• 01: Full - Incremental (407f0381)
• 00: Full (7275a7b1)

[openjdk-notifier]

The parent pull request that this pull request depends on has now been integrated and the target branch of this pull request has been updated. This means that changes from the dependent pull request can start to show up as belonging to this pull request, which may be confusing for reviewers. To remedy this situation, simply merge the latest changes from the new target branch into this pull request by running commands similar to these in the local repository for your personal fork:

git checkout submit/8294847-fix-effective-cards-calculation
git fetch https://git.openjdk.org/jdk master
git merge FETCH_HEAD
# if there are conflicts, follow the instructions given by git merge
git commit -m "Merge master"
git push

[kimbarrett]

Looks good.

[openjdk]

@tschatzl 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:

8294847: Fix calculation of G1 effective scanned cards prediction

Reviewed-by: kbarrett, ayang

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 21 new commits pushed to the master branch:

• 2f60675: 8294997: Improve ECC math operations
• 94caecb: 8294906: Memory leak in PKCS11 NSS TLS server
• 03e63a2: 8295225: [JVMCI] codeStart should be cleared when entryPoint is cleared
• 26ac836: 8291638: Keep-Alive timeout of 0 should close connection immediately
• 6ae7e4d: 8293984: Unnecessary Vector usage in PropertyEditorSupport
• cd1357b: 8295229: Try to verify gtest version
• 90fb9a0: 8295102: Always load @lambda-form-invoker lines from default classlist
• ac19414: 8294994: Update Jarsigner and Keytool i18n tests to validate i18n compliance
• 1961e81: 8289509: Improve test coverage for XPath Axes: descendant, descendant-or-self, following, following-sibling
• 5699041: 8294772: Remove workaround in os::dll_address_to_library_name
• ... and 11 more: https://git.openjdk.org/jdk/compare/bdb4ed0fb136e9e5391cfa520048de6b7f83067d...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.

[tschatzl]

Thanks @kimbarrett @albertnetymk for your reviews.

/integrate

[openjdk]

Going to push as commit 7e4868d.
Since your change was applied there have been 21 commits pushed to the master branch:

• 2f60675: 8294997: Improve ECC math operations
• 94caecb: 8294906: Memory leak in PKCS11 NSS TLS server
• 03e63a2: 8295225: [JVMCI] codeStart should be cleared when entryPoint is cleared
• 26ac836: 8291638: Keep-Alive timeout of 0 should close connection immediately
• 6ae7e4d: 8293984: Unnecessary Vector usage in PropertyEditorSupport
• cd1357b: 8295229: Try to verify gtest version
• 90fb9a0: 8295102: Always load @lambda-form-invoker lines from default classlist
• ac19414: 8294994: Update Jarsigner and Keytool i18n tests to validate i18n compliance
• 1961e81: 8289509: Improve test coverage for XPath Axes: descendant, descendant-or-self, following, following-sibling
• 5699041: 8294772: Remove workaround in os::dll_address_to_library_name
• ... and 11 more: https://git.openjdk.org/jdk/compare/bdb4ed0fb136e9e5391cfa520048de6b7f83067d...master

Your commit was automatically rebased without conflicts.

[openjdk]

@tschatzl Pushed as commit 7e4868d.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.