Fix [BUG] ClusterMaxMergesAtOnceIT is flaky by laminelam · Pull Request #19647 · opensearch-project/OpenSearch

laminelam · 2025-10-15T21:02:08Z

Resolves #18056

[BUG] ClusterMaxMergesAtOnceIT is flaky

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.

Summary by CodeRabbit

Bug Fixes
- Improved test reliability by fixing an intermittent failure in cluster merge-policy validation; this reduces spurious test failures and improves CI stability.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

update change log Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

github-actions · 2025-10-15T23:02:55Z

✅ Gradle check result for 17e5f99: SUCCESS

codecov · 2025-10-15T23:03:19Z

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.21%. Comparing base (d47931e) to head (7701d2c).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #19647      +/-   ##
============================================
- Coverage     73.30%   73.21%   -0.09%     
+ Complexity    71732    71706      -26     
============================================
  Files          5793     5793              
  Lines        328056   328110      +54     
  Branches      47245    47256      +11     
============================================
- Hits         240476   240228     -248     
- Misses        68264    68595     +331     
+ Partials      19316    19287      -29

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

laminelam · 2025-10-20T20:22:30Z

Hi @andrross
Do you have time to review this?

server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java

laminelam · 2025-11-02T12:12:10Z

Hi @msfroh
Can you please give this a second look? Hope my previous comments answer your question.

andrross · 2025-11-21T22:25:51Z

Hi @msfroh Can you please give this a second look? Hope my previous comments answer your question.

@laminelam I don't see any response from you on this PR. Can you address the questions raised here?

Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

coderabbitai · 2025-12-08T01:07:40Z

Walkthrough

Removed the test workaround and made the third index creation explicit by wrapping it with assertAcked(prepareCreate(...)), and added a changelog entry documenting the fix for ClusterMaxMergesAtOnceIT.testClusterLevelDefaultUpdatesMergePolicy.

Changes

Cohort / File(s)	Change Summary
Changelog `CHANGELOG.md`	Added a Fixed entry documenting the fix for the flaky test ClusterMaxMergesAtOnceIT.testClusterLevelDefaultUpdatesMergePolicy (`#18056`).
Test synchronization & cleanup `server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java`	Removed `@AwaitsFix` from `testClusterLevelDefaultUpdatesMergePolicy`; added static import for `assertAcked`; changed third index creation to `assertAcked(prepareCreate(indexName, Settings.builder(...)))` to ensure proper index creation synchronization; minor formatting adjustments.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Review the modified test method for correct use of assertAcked and Settings builder.
Verify removal of @AwaitsFix is appropriate and no other tests rely on it.
Check the changelog addition for correct formatting and placement.

Poem

🐰 A jittery test hopped into the night,
I wrapped its nest with assertAcked tight,
The nulls ran off, the merges mend,
Now CI sleeps and dreams ascend,
Hooray — one less flaky fright! 🥕✨

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run `@coderabbitai generate docstrings` to improve docstring coverage.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically describes the main change: fixing a flaky test in ClusterMaxMergesAtOnceIT.
Description check	✅ Passed	The description identifies the related issue (#18056) and states the fix resolves the flaky test, but lacks specific details about what changes were made to resolve the flakiness.
Linked Issues check	✅ Passed	The PR addresses the core requirements from issue #18056: it fixes the flaky test by removing the AwaitsFix annotation and fixing the NullPointerException issue with the third IndexService.
Out of Scope Changes check	✅ Passed	All changes are directly scoped to fixing the flaky test issue: CHANGELOG.md entry documents the fix, and ClusterMaxMergesAtOnceIT.java contains the actual test fix.

✨ Finishing touches

🧪 Generate unit tests (beta)

Create PR with unit tests
Post copyable unit tests in a comment

📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 9154fe7 and 7701d2c.

📒 Files selected for processing (1)

CHANGELOG.md (1 hunks)

🚧 Files skipped from review as they are similar to previous changes (1)

CHANGELOG.md

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (21)

GitHub Check: gradle-check
GitHub Check: Analyze (java)
GitHub Check: detect-breaking-change
GitHub Check: precommit (21, macos-15)
GitHub Check: precommit (25, ubuntu-24.04-arm)
GitHub Check: precommit (25, ubuntu-latest)
GitHub Check: precommit (25, macos-15)
GitHub Check: precommit (21, windows-2025, true)
GitHub Check: precommit (25, macos-15-intel)
GitHub Check: precommit (21, ubuntu-24.04-arm)
GitHub Check: precommit (21, windows-latest)
GitHub Check: precommit (25, windows-latest)
GitHub Check: precommit (21, ubuntu-latest)
GitHub Check: precommit (21, macos-15-intel)
GitHub Check: assemble (21, ubuntu-24.04-arm)
GitHub Check: Mend Security Check
GitHub Check: assemble (25, ubuntu-latest)
GitHub Check: assemble (21, ubuntu-latest)
GitHub Check: assemble (25, ubuntu-24.04-arm)
GitHub Check: assemble (21, windows-latest)
GitHub Check: assemble (25, windows-latest)

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

coderabbitai

Actionable comments posted: 0

🧹 Nitpick comments (1)

CHANGELOG.md (1)

23-30: Changelog entry looks good; consider aligning link style with neighbors

The new Fixed entry clearly documents the flaky-test fix and links the underlying issue. If this project’s convention is to reference PRs in the changelog (as neighboring lines do), you may want to either:

Switch this to the PR URL, or

Include both issue and PR numbers for consistency.

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 387e663 and 9154fe7.

📒 Files selected for processing (2)

CHANGELOG.md (1 hunks)
server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java (2 hunks)

🧰 Additional context used

🧬 Code graph analysis (1)

server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java (1)

server/src/main/java/org/opensearch/index/TieredMergePolicyProvider.java (1)

TieredMergePolicyProvider (132-328)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

GitHub Check: gradle-check

🔇 Additional comments (2)

server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java (2)

50-52: assertAcked import is appropriate for the new index-creation pattern

The static import of assertAcked matches the updated usage below and keeps the test code concise.

99-106: Verification inconclusive—please provide code context or test results

The claim that switching to assertAcked(prepareCreate(...)) fixes the NPE by ensuring replica settings are applied requires confirmation. The logical connection between a merge policy setting override and replica presence on data nodes is unclear. Please either:

Share the full test method and baseIndexSettings() definition to confirm how settings are applied

Provide test execution results demonstrating stability with the seed 2BD0981DD7D9F5EF before and after this change

github-actions · 2025-12-08T02:11:10Z

❌ Gradle check result for 9154fe7: FAILURE

Please examine the workflow log, locate, and copy-paste the failure(s) below, then iterate to green. Is the failure a flaky test unrelated to your change?

github-actions · 2025-12-08T03:53:40Z

✅ Gradle check result for 7701d2c: SUCCESS

* Fix flack test opensearch-project#18056 Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com> * remove AwaitsFix annotation update change log Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com> * use prepareCreate to merge with setup settings Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com> --------- Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com> Co-authored-by: Lamine Idjeraoui <lidjeraoui@apple.com>

Fix flack test opensearch-project#18056

569ee65

Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

laminelam requested review from a team, Bukhtawar, CEHENKLE, Rishikesh1159, anasalkouz, andrross, ashking94, cwperks, dbwiddis, gbbafna, jed326, kotwanikunal, mch2, msfroh, owaiskazi19, reta, sachinpkale, saratvemulapalli, shwetathareja and sohami as code owners October 15, 2025 21:02

github-actions bot added bug Something isn't working disabled-test Issues that are used by an AwaitsFix annotation to temporarily disable a broken test flaky-test Random test failure that succeeds on second run Indexing Indexing, Bulk Indexing and anything related to indexing labels Oct 15, 2025

Merge remote-tracking branch 'ApacheFork/main' into flacky/test1

88f189f

remove AwaitsFix annotation

17e5f99

update change log Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

msfroh reviewed Oct 20, 2025

View reviewed changes

server/src/internalClusterTest/java/org/opensearch/index/ClusterMaxMergesAtOnceIT.java Outdated Show resolved Hide resolved

laminelam requested a review from msfroh November 2, 2025 12:10

use prepareCreate to merge with setup settings

9154fe7

Signed-off-by: Lamine Idjeraoui <lidjeraoui@apple.com>

coderabbitai bot reviewed Dec 8, 2025

View reviewed changes

Lamine Idjeraoui added 2 commits December 7, 2025 20:31

Merge branch 'main' into flacky/test1

a298261

Merge branch 'main' into flacky/test1

7701d2c

andrross approved these changes Dec 8, 2025

View reviewed changes

andrross merged commit e3a1533 into opensearch-project:main Dec 8, 2025
35 checks passed

coderabbitai bot mentioned this pull request Dec 23, 2025

[RFC] Reproduce the corruption issue in the segment replication scenario with soft delete enabled. #20312

Open

opensearch-ci-bot mentioned this pull request Feb 18, 2026

[AUTOCUT] Gradle Check Flaky Test Report for SharedClusterSnapshotRestoreIT #15845

Open

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Fix [BUG] ClusterMaxMergesAtOnceIT is flaky#19647

Fix [BUG] ClusterMaxMergesAtOnceIT is flaky#19647
andrross merged 6 commits intoopensearch-project:mainfrom
laminelam:flacky/test1

laminelam commented Oct 15, 2025 •

edited by coderabbitai bot

Loading

Uh oh!

github-actions bot commented Oct 15, 2025

Uh oh!

codecov bot commented Oct 15, 2025 •

edited

Loading

Uh oh!

laminelam commented Oct 20, 2025

Uh oh!

Uh oh!

laminelam commented Nov 2, 2025

Uh oh!

andrross commented Nov 21, 2025

Uh oh!

coderabbitai bot commented Dec 8, 2025 •

edited

Loading

Uh oh!

coderabbitai bot left a comment

Uh oh!

github-actions bot commented Dec 8, 2025

Uh oh!

github-actions bot commented Dec 8, 2025

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Conversation

laminelam commented Oct 15, 2025 • edited by coderabbitai bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Summary by CodeRabbit

Uh oh!

github-actions bot commented Oct 15, 2025

Uh oh!

codecov bot commented Oct 15, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Codecov Report

Uh oh!

laminelam commented Oct 20, 2025

Uh oh!

Uh oh!

laminelam commented Nov 2, 2025

Uh oh!

andrross commented Nov 21, 2025

Uh oh!

coderabbitai bot commented Dec 8, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Walkthrough

Changes

Estimated code review effort

Poem

Pre-merge checks and finishing touches

Uh oh!

coderabbitai bot left a comment

Choose a reason for hiding this comment

Uh oh!

github-actions bot commented Dec 8, 2025

Uh oh!

github-actions bot commented Dec 8, 2025

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

laminelam commented Oct 15, 2025 •

edited by coderabbitai bot

Loading

codecov bot commented Oct 15, 2025 •

edited

Loading

coderabbitai bot commented Dec 8, 2025 •

edited

Loading