metrics: dynamic stream add batch related metrics and storage sink add metrics

[3AceShowHand]

What problem does this PR solve?

Issue Number: close #4029

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

`None`

[gemini-code-assist]

Summary of Changes

Hello @3AceShowHand, 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 significantly enhances the observability of the dynamic stream component by introducing detailed batch-level metrics. It adds new Prometheus histograms to track the count of events, total bytes, and processing duration for each batch. These additions provide critical insights into the performance and efficiency of event handling, facilitating better monitoring and debugging of the dynamic stream's operational characteristics.

Highlights

• New Batch Metrics: Introduced three new Prometheus histogram metrics: DynamicStreamBatchCount, DynamicStreamBatchBytes, and DynamicStreamBatchDuration to monitor batch processing within the dynamic stream component. These metrics track the number of events, total bytes, and processing duration per batch, respectively.
• Event Queue Modification: The popEvents function in event_queue.go was updated to return the total number of bytes processed in a batch, enabling more comprehensive metric collection.
• Metric Integration: Integrated the recording of these new batch metrics into the stream.handleLoop function, ensuring that batch size, byte count, and processing duration are captured and exposed via Prometheus.
• Metric Labeling: Added an areaStr field to the pathInfo struct, which is used as a label for the new batch metrics, allowing for more granular monitoring.

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[gemini-code-assist]

Code Review

This pull request adds batch metrics to dynstream. The changes are generally good, but I've found a critical issue that could cause a panic due to a nil pointer dereference, as well as an issue with an incorrect time unit for a duration metric. Additionally, there's a minor inconsistency in metric labeling that should be addressed for better clarity. My detailed feedback and suggestions are in the comments below.

[3AceShowHand]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces batch metrics for dynstream, which is a great addition for observability. The changes include defining new Prometheus metrics, updating the dynstream handler interface to provide metric labels, and implementing this in various handlers. The core logic for collecting metrics in dynstream seems correct. I've found a couple of areas for improvement: one regarding code duplication in handler implementations and another a potential issue with empty metric labels. Overall, this is a solid contribution.

[3AceShowHand]

/test ?

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[3AceShowHand]

/test all

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2026-01-20 08:27:37.796379016 +0000 UTC m=+482485.410335862: ☑️ agreed by asddongmen.
• 2026-01-20 08:32:38.309339077 +0000 UTC m=+482785.923295933: ☑️ agreed by wk989898.

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: asddongmen, wk989898

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