Hdds 13999

[ChenSammi]

What changes were proposed in this pull request?

Provide a one-liner summary of the changes in the PR Title field above.
It should be in the form of HDDS-1234. Short summary of the change.

Please describe your PR in detail:

• What changes are proposed in the PR? and Why? It would be better if it is written from third person's
  perspective not just for the reviewer.
• Provide as much context and rationale for the pull request as possible. It could be copy-paste from
  the Jira's description if the jira is well defined.
• If it is complex code, describe the approach used to solve the issue. If possible attach design doc,
  issue investigation, github discussion, etc.

Examples of well-written pull requests:

• #3980
• #5265
• #4701
• #5283
• #5300

What is the link to the Apache JIRA

Please create an issue in ASF JIRA before opening a pull request, and you need to set the title of the pull
request which starts with the corresponding JIRA issue number. (e.g. HDDS-XXXX. Fix a typo in YYY.)

(Please replace this section with the link to the Apache JIRA)

How was this patch tested?

(Please explain how this patch was tested. Ex: unit tests, manual tests, workflow run on the fork git repo.)
(If this patch involves UI changes, please attach a screenshot; otherwise, remove this.)

[gemini-code-assist]

Summary of Changes

Hello @ChenSammi, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request introduces significant improvements across several core Ozone components, focusing on enhancing stability, observability, and configurability. It modernizes the distributed tracing system by migrating to OpenTelemetry, addresses potential memory issues with a new bounded byte buffer pool, and refines the container reconciliation process to better handle deleted blocks. Additionally, it provides more flexible RocksDB configuration options for datanodes and optimizes the handling of pipeline commands.

Highlights

• OpenTelemetry Migration: The distributed tracing infrastructure has been migrated from the deprecated OpenTracing/Jaeger to OpenTelemetry. This involves updating dependencies and adapting tracing utilities to the new standard, ensuring future compatibility and improved observability.
• Bounded ByteBuffer Pool: A new BoundedElasticByteBufferPool has been introduced to prevent unbounded memory growth in long-lived RPC clients, such as the S3 Gateway. This pool limits the total size of cached buffers, ensuring that excess buffers are garbage collected.
• Container Checksum Tree Enhancements: The container checksum tree management logic has been refined to handle deleted blocks more robustly during reconciliation. This ensures proper convergence of replica states, even when blocks are deleted on some datanodes but not others.
• Datanode RocksDB Configuration: Datanodes can now load RocksDB configuration from an external .ini file, allowing for more flexible and granular tuning of database options and column family settings.
• Pipeline Command Processing Improvements: Close and Create Pipeline commands now utilize dedicated, bounded thread pools and include deduplication logic. This prevents redundant processing of commands and improves the efficiency and stability of pipeline management.
• Snapshot Defragmentation Feature: New configuration keys and a command for snapshot defragmentation have been added, laying the groundwork for an upcoming feature aimed at optimizing snapshot storage efficiency.

Ignored Files

• Ignored by pattern: .github/workflows/** (4)
  • .github/workflows/check.yml
  • .github/workflows/ci.yml
  • .github/workflows/close-stale-prs.yaml
  • .github/workflows/intermittent-test-check.yml

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[gemini-code-assist]

Code Review

This pull request introduces a wide range of significant changes and improvements across the codebase. Key changes include a migration from OpenTracing to OpenTelemetry for distributed tracing, a major refactoring of the container merkle tree to better handle deleted blocks, and enhancements to RDB batch operations to support delete ranges. Additionally, there are performance improvements in the ContainerSet, better resource management for pipeline command handlers, and numerous bug fixes and code cleanups. The overall quality of the changes is high, and they represent substantial progress for the project. I have one minor suggestion for removing some dead code.

[gemini-code-assist]

The local variable flushPeriod is calculated here but is never used. This appears to be dead code and should be removed to improve clarity and avoid confusion for future maintainers.