Add context for custom GC tunings

[andrross]

Related Issues

Resolves #11649

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

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.

[github-actions]

Compatibility status:

Checks if related components are compatible with change 45d22d7

Incompatible components

Incompatible components: [https://github.com/opensearch-project/performance-analyzer.git, https://github.com/opensearch-project/performance-analyzer-rca.git]

Skipped components

Compatible components

Compatible components: [https://github.com/opensearch-project/asynchronous-search.git, https://github.com/opensearch-project/security-analytics.git, https://github.com/opensearch-project/observability.git, https://github.com/opensearch-project/notifications.git, https://github.com/opensearch-project/reporting.git, https://github.com/opensearch-project/job-scheduler.git, https://github.com/opensearch-project/opensearch-oci-object-storage.git, https://github.com/opensearch-project/neural-search.git, https://github.com/opensearch-project/common-utils.git, https://github.com/opensearch-project/custom-codecs.git, https://github.com/opensearch-project/geospatial.git, https://github.com/opensearch-project/anomaly-detection.git, https://github.com/opensearch-project/ml-commons.git, https://github.com/opensearch-project/security.git, https://github.com/opensearch-project/index-management.git, https://github.com/opensearch-project/k-nn.git, https://github.com/opensearch-project/alerting.git, https://github.com/opensearch-project/cross-cluster-replication.git, https://github.com/opensearch-project/sql.git]

[github-actions]

❕ Gradle check result for 45d22d7: UNSTABLE

• TEST FAILURES:

      1 org.opensearch.search.SearchWeightedRoutingIT.testMultiGetWithNetworkDisruption_FailOpenEnabled
      1 org.opensearch.remotestore.multipart.RemoteStoreMultipartIT.testNoSearchIdleForAnyReplicaCount
      1 org.opensearch.remotestore.RemoteIndexPrimaryRelocationIT.testPrimaryRelocationWhileIndexing
      1 org.opensearch.indices.state.CloseWhileRelocatingShardsIT.testCloseWhileRelocatingShards

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f1243ea) 71.28% compared to head (45d22d7) 71.35%.

Additional details and impacted files

@@             Coverage Diff              @@
##               main   #11651      +/-   ##
============================================
+ Coverage     71.28%   71.35%   +0.07%     
- Complexity    59139    59157      +18     
============================================
  Files          4906     4906              
  Lines        278184   278184              
  Branches      40421    40421              
============================================
+ Hits         198296   198507     +211     
+ Misses        63376    63178     -198     
+ Partials      16512    16499      -13     

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