Optimize remote store operations during snapshot Deletion

[harishbhakuni]

Description

• Optimize stale segments deletion method [StaleSegmentsDeletion(int lastNmdFilesToKeep)]:
  • Current approach:
    1. read all the non deletable (locked or in last N md files) md files to get active segments,
    2. for each deletable (not locked or not in last N md files) md file,
       1. read md file to get segments and filter the active segments (fetched in (a)),
       2. delete the non active segments one by one.
    3. if all the non active segments for md file deleted, delete the md file.
  • Optimized approach:
    1. since each remote store md file is snapshot of live segments at the time of its creation, we can assume that (1) if a segment file is not present in a md file, it will never be present in any md file after that and (2) if (md1, md2, md3) are in sorted order, it is not possible that a segment file will be in md1 and md3 but not in md2.
    2. for each deletable md file, we can consider the segments present in non deletable md file before this and non deletable md file after this as the active segments for this. so, to filter out non active segment files for a deletable metadata file, we just need to read the non deletable md file before and after this md file.
    3. we can batch delete the non active segment files for each deletable md file.
    4. we can batch delete the md files for which non active segment files delete successfully.
• Lazy initialize the remote directory instance as part of remote_purge threadpool task itself, so that we create/initialize the instance only once the task is picked up for execution.
• Optimize snapshot deletion logic to skip only the shard blob deletion for which remote store cleanup failed.
• Maintain a local cache to track successful remote store operations which would avoid multiple calls for same resource cleanup.

Related Issues

#12302,
#12253

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 79ef792: 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]

Compatibility status:

Checks if related components are compatible with change f69acff

Incompatible components

Skipped components

Compatible components

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

[github-actions]

❌ Gradle check result for a50df48: 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]

❌ Gradle check result for ca5d929: 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]

❌ Gradle check result for 97c6ead: 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]

✅ Gradle check result for 5475951: SUCCESS

[github-actions]

✅ Gradle check result for 488c81c: SUCCESS

[github-actions]

❌ Gradle check result for 5ba410b: 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?

[ashking94]

Lets add more cases for the RemoteStoreShardCleanupTask covering concurrent clean up tasks.

[github-actions]

✅ Gradle check result for f69acff: SUCCESS

[opensearch-trigger-bot]

The backport to 2.x failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.x 2.x
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.x
# Create a new branch
git switch --create backport/backport-12319-to-2.x
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 b26521562b2c51991f30a75c7d266d4be8e2b3de
# Push it to GitHub
git push --set-upstream origin backport/backport-12319-to-2.x
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.x

Then, create a pull request where the base branch is 2.x and the compare/head branch is backport/backport-12319-to-2.x.

[opensearch-trigger-bot]

The backport to 2.11 failed:

The process '/usr/bin/git' failed with exit code 128

To backport manually, run these commands in your terminal:

# Navigate to the root of your repository
cd $(git rev-parse --show-toplevel)
# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add ../.worktrees/OpenSearch/backport-2.11 2.11
# Navigate to the new working tree
pushd ../.worktrees/OpenSearch/backport-2.11
# Create a new branch
git switch --create backport/backport-12319-to-2.11
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick -x --mainline 1 b26521562b2c51991f30a75c7d266d4be8e2b3de
# Push it to GitHub
git push --set-upstream origin backport/backport-12319-to-2.11
# Go back to the original working tree
popd
# Delete the working tree
git worktree remove ../.worktrees/OpenSearch/backport-2.11

Then, create a pull request where the base branch is 2.11 and the compare/head branch is backport/backport-12319-to-2.11.