Add blog post: Achieving Sub-Millisecond Proxy Overhead

[AlexsanderHamir]

Relevant issues

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Type

📖 Documentation

Changes

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Project	Deployment	Actions	Updated (UTC)
litellm	Building	Preview, Comment	Feb 3, 2026 1:46am

[greptile-apps]

Greptile Overview

Greptile Summary

This PR adds a new blog post announcing LiteLLM's Q1 performance target: achieving sub-millisecond proxy overhead on modest hardware (4 CPUs, 8 GB RAM). The post introduces an optional sidecar architecture where Python handles the control plane (validation, routing, callbacks) while a sidecar handles performance-critical execution (request forwarding, connection pooling, timeouts).

Key Points:

• Establishes baseline performance: LiteLLM now handles 1,000-5,000 QPS without failures (previously failed at 1,000 QPS)
• Announces architectural direction: optional sidecar for hot-path optimization
• Sidecar is bundled, auto-started, and can be disabled - no additional infrastructure required
• No actual implementation code included in this PR (documentation only)

Minor Issues:

• Blog post date may need updating (set to Feb 2 but committed Feb 3)
• Image hosted on personal GitHub account rather than official repository

Confidence Score: 4/5

• This documentation-only PR is safe to merge with only minor formatting concerns
• The PR adds a well-written blog post with no code changes. The only concerns are a potential date mismatch and an image URL pointing to a personal GitHub account. No functional risks.
• No files require special attention

Important Files Changed

Filename	Overview
docs/my-website/blog/sub_millisecond_proxy_overhead/index.md	New blog post announcing Q1 performance goals and sidecar architecture for achieving sub-millisecond proxy overhead

Sequence Diagram

sequenceDiagram
    participant Client
    participant Python as Python Control Plane
    participant Sidecar as Sidecar (Optional)
    participant Provider as LLM Provider

    Note over Python,Sidecar: Sidecar Architecture (Optional)
    
    Client->>Python: Incoming Request
    Python->>Python: Request Validation
    Python->>Python: Model/Provider Selection
    Python->>Python: Execute Callbacks
    
    alt Sidecar Enabled
        Python->>Sidecar: Forward Request
        Sidecar->>Provider: Efficient Forwarding
        Sidecar->>Sidecar: Connection Pooling
        Sidecar->>Sidecar: Enforce Timeouts
        Provider->>Sidecar: Response
        Sidecar->>Python: Response
    else Sidecar Disabled
        Python->>Provider: Direct Request
        Provider->>Python: Response
    end
    
    Python->>Python: Execute Callbacks
    Python->>Client: Final Response

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[greptile-apps]

_{1 file reviewed, 2 comments}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

The date is set to 2026-02-02, but today is 2026-02-03. Check if this is intentional or should be updated.

Suggested change

	date: 2026-02-02T10:00:00
	date: 2026-02-03T10:00:00

Prompt To Fix With AI

This is a comment left during a code review.
Path: docs/my-website/blog/sub_millisecond_proxy_overhead/index.md
Line: 4:4

Comment:
The date is set to 2026-02-02, but today is 2026-02-03. Check if this is intentional or should be updated.

```suggestion
date: 2026-02-03T10:00:00
```

How can I resolve this? If you propose a fix, please make it concise.

[greptile-apps]

Image URL points to a personal GitHub account (AlexsanderHamir/assets). Consider hosting in the official LiteLLM repository for long-term stability.

_{Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!}

Prompt To Fix With AI

This is a comment left during a code review.
Path: docs/my-website/blog/sub_millisecond_proxy_overhead/index.md
Line: 23:23

Comment:
Image URL points to a personal GitHub account (`AlexsanderHamir/assets`). Consider hosting in the official LiteLLM repository for long-term stability.

<sub>Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!</sub>

How can I resolve this? If you propose a fix, please make it concise.