fix: SGLang component names to match worker registration patterns

[GavinZhu-GMI]

Overview:

SGLang planner cannot detect SGLang workers due to component name mismatch, preventing autoscaling functionality.

Details:

The SGLang planner expects workers at:

• Prefill: instances/dynamo/worker/generate
• Decode: instances/dynamo/decode/generate

But SGLang workers actually register at:

• Default: instances/dynamo/backend/generate
• Prefill mode: instances/dynamo/prefill/generate

Where should the reviewer start?

components/planner/src/dynamo/planner/defaults.py

Related Issues: (use one of the action keywords Closes / Fixes / Resolves / Relates to)

• closes GitHub issue: [BUG]: SGLang Planner Cannot Detect Workers Due to Component Name Mismatch #3106

Summary by CodeRabbit

• Refactor
  • Standardized component names: the prefill worker is now labeled “prefill,” and the decode worker is now labeled “backend.”
  • Improves consistency across services for clearer identification in dashboards, logs, and configurations.
  • If you reference the old labels in custom configs, monitors, or scripts, update them to the new names.

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[github-actions]

👋 Hi GavinZhu-GMI! Thank you for contributing to ai-dynamo/dynamo.

Just a reminder: The NVIDIA Test Github Validation CI runs an essential subset of the testing framework to quickly catch errors.Your PR reviewers may elect to test the changes comprehensively before approving your changes.

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[coderabbitai]

Walkthrough

Updated two string attributes in SGLangComponentName within components/planner/src/dynamo/planner/defaults.py: prefill_worker_component_name set to "prefill" (was "worker") and decode_worker_component_name set to "backend" (was "decode".) No other fields were changed.

Changes

Cohort / File(s)	Summary of Changes
Planner defaults adjustments components/planner/src/dynamo/planner/defaults.py	Updated SGLangComponentName: prefill_worker_component_name "worker" → "prefill"; decode_worker_component_name "decode" → "backend". No other attribute changes.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

Possibly related issues

• [BUG]: SGLang Planner Cannot Detect Workers Due to Component Name Mismatch #3106 — Aligns prefill/decode worker component names with worker registration names by updating the two attributes in defaults.py.

Poem

I twitch my whiskers, tiny QA knight,
Renamed two strings, set labels right.
From worker to prefill, backend in tow,
Pipelines hop smoother wherever they go.
Carrot commit sealed, tests in the light—
Thump-thump, the planner’s ready for flight! 🥕🐇

Pre-merge checks

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description Check	✅ Passed	The PR description follows the repository template and includes the required sections: Overview, Details, Where should the reviewer start, and Related Issues with "closes GitHub issue: #3106". The Details clearly explain the component-name mismatch, list the expected vs actual registration names, and point reviewers to components/planner/src/dynamo/planner/defaults.py. It would be slightly stronger with a brief note about tests or rollout impact, but it is otherwise complete and actionable.
Docstring Coverage	✅ Passed	No functions found in the changes. Docstring coverage check skipped.
Title Check	✅ Passed	The title succinctly and accurately describes the primary change: updating SGLang component names to match worker registration patterns. It is concise, specific to the subsystem, and avoids extraneous details or vague wording. This directly reflects the PR objectives and the changes in components/planner/src/dynamo/planner/defaults.py that align planner defaults with worker registration names.

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[PeaBrane]

Nice catch!

[PeaBrane]

/ok to test 0c126ff