# Trace requests through vLLM v1

**URL:** <https://discuss.vllm.ai/t/trace-requests-through-vllm-v1/721>\
**Category:** General\
**Created:** [May 29, 2025, 4:01pm UTC](https://discuss.vllm.ai/t/trace-requests-through-vllm-v1/721 "2025-05-29T16:01:13Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![sagoyal](https://avatars.discourse-cdn.com/v4/letter/s/f0a364/32.png) [@sagoyal](https://discuss.vllm.ai/u/sagoyal)\
**Post date:** [May 29, 2025, 4:01pm UTC](https://discuss.vllm.ai/t/trace-requests-through-vllm-v1/721/1 "2025-05-29T16:01:13Z")

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Hi Everyone,

I am trying to understand how requests go through vLLM v1 almost at function level. Is the best way to look at this just explore the source code here: [vllm/vllm/v1 at main · vllm-project/vllm · GitHub](https://github.com/vllm-project/vllm/tree/main/vllm/v1)

Are there any other good docs that helps me understand a level deeper than the docs here: [vLLM V1: A Major Upgrade to vLLM’s Core Architecture | vLLM Blog](https://blog.vllm.ai/2025/01/27/v1-alpha-release.html)

Thanks,  
Satyam

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<div class="post-metadata">

**Author:** ![RunLLM](https://yyz2.discourse-cdn.com/flex036/user_avatar/discuss.vllm.ai/runllm/32/233_2.png) [@RunLLM](https://discuss.vllm.ai/u/RunLLM)\
**Post date:** [May 29, 2025, 4:01pm UTC](https://discuss.vllm.ai/t/trace-requests-through-vllm-v1/721/2 "2025-05-29T16:01:42Z")

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For a function-level understanding of how requests flow through vLLM v1, the best starting point is indeed the source code in [vllm/vllm/v1 at main · vllm-project/vllm · GitHub](https://github.com/vllm-project/vllm/tree/main/vllm/v1). However, there are also helpful architecture and API docs that provide more detail than the blog post. The [vLLM V1 User Guide](https://docs.vllm.ai/en/stable/getting_started/v1_user_guide.html) and the [Architecture Overview](https://docs.vllm.ai/en/stable/design/arch_overview.html) explain the main components, entrypoints, and request flow, while the [API reference for v1](https://docs.vllm.ai/en/latest/api/vllm/vllm.v1.html) lists the submodules and classes.

For even deeper insight, the [architecture overview on GitHub](https://github.com/vllm-project/vllm/blob/main/docs/design/arch_overview.md) describes the LLMEngine, AsyncLLMEngine, and worker processes, and the [multiprocessing design doc](https://docs.vllm.ai/en/stable/design/multiprocessing.html) explains process management. These resources, combined with the source code, will give you a comprehensive, function-level view of request handling in vLLM v1.

Would you like a step-by-step breakdown of the request flow at the function level?

Sources:

- [vLLM V1 User Guide](https://docs.vllm.ai/en/stable/getting_started/v1_user_guide.html)
- [Architecture Overview](https://docs.vllm.ai/en/stable/design/arch_overview.html)
- [Architecture overview on GitHub](https://github.com/vllm-project/vllm/blob/main/docs/design/arch_overview.md)
- [vLLM v1 blog post](https://blog.vllm.ai/2025/01/27/v1-alpha-release.html)
- [API reference for v1](https://docs.vllm.ai/en/latest/api/vllm/vllm.v1.html)