Fix Flaky test IndicesRequestCacheIT.testStaleKeysCleanupWithMultipleIndices

[kiranprakash154]

Description

Fix Flaky test IndicesRequestCacheIT.testStaleKeysCleanupWithMultipleIndices. failing with java.lang.AssertionError: expected:<-665> but was:<665>

In the below code, memorySizeOfLatestEntryForIndex1 would be negative (-665) if the cacheCleaner ran before the execution of that line resulting in getRequestCacheStats(client, index1).getMemorySizeInBytes() to be smaller than finalMemorySizeForIndex1

long memorySizeOfLatestEntryForIndex1 = getRequestCacheStats(client, index1).getMemorySizeInBytes() - finalMemorySizeForIndex1;
.
.
.
assertEquals(memorySizeOfLatestEntryForIndex1, getRequestCacheStats(client, index1).getMemorySizeInBytes())

What is the Fix ?

The fix is to not depend on the exact size of the memorySizeOfLatestEntryForIndex1 and instead make sure the current request cache stats size is less than memorySizeForIndex1With2Entries and > 0
By this, we avoid the race condition of cacheCleaner being invoked before the calculation of memorySizeOfLatestEntryForIndex1

Related Issues

Resolves #13437

Check List

• New functionality includes testing.
  • All tests pass
• New functionality has been documented.
  • New functionality has javadoc added
• Failing checks are inspected and point to the corresponding known issue(s) (See: Troubleshooting Failing Builds)
• Commits are signed per the DCO using --signoff
• Commit changes are listed out in CHANGELOG.md file (See: Changelog)
• Public documentation issue/PR created

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[github-actions]

❌ Gradle check result for d81d42a: 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?

[kiranprakash154]

❌ Gradle check result for d81d42a: 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?

Tests with failures:

• org.opensearch.snapshots.CloneSnapshotIT.testShallowCloneNameAvailability - [BUG] flaky org.opensearch.snapshots.CloneSnapshotIT.testShallowCloneNameAvailability test #10155
• org.opensearch.remotemigration.RemoteReplicaRecoveryIT.testReplicaRecovery - [Remote Store] Mute RemoteIndexRecoveryIT.testReplicaRecovery flaky test #9682 & [BUG] [Remote Store] fix IndexRecoveryIT to work with Remote Store enabled clusters #8919

[github-actions]

✅ Gradle check result for d81d42a: SUCCESS

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 71.46%. Comparing base (b15cb0c) to head (5b6926e).
Report is 239 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #13453      +/-   ##
============================================
+ Coverage     71.42%   71.46%   +0.04%     
- Complexity    59978    60839     +861     
============================================
  Files          4985     5046      +61     
  Lines        282275   286108    +3833     
  Branches      40946    41432     +486     
============================================
+ Hits         201603   204470    +2867     
- Misses        63999    64786     +787     
- Partials      16673    16852     +179     

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[github-actions]

❕ Gradle check result for 5b6926e: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.index.IndexServiceTests.testAsyncTranslogTrimTaskOnClosedIndex

Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

[kiranprakash154]

❕ Gradle check result for 5b6926e: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.index.IndexServiceTests.testAsyncTranslogTrimTaskOnClosedIndex

Please review all flaky tests that succeeded after retry and create an issue if one does not already exist to track the flaky failure.

Known Flaky #11547

[kiranprakash154]

@dblock can u merge this ?
(cc: @kkhatua )

[dblock]

Happened again in #13655.