docs: init readthedocs support (#783)

This commit is contained in:
Yineng Zhang
2024-07-28 16:50:31 +10:00
committed by GitHub
parent 68e5262699
commit 948625799e
16 changed files with 246 additions and 6 deletions

View File

@@ -1,16 +0,0 @@
# How to Support a New Model
To support a new model in SGLang, you only need to add a single file under [SGLang Models Directory](https://github.com/sgl-project/sglang/tree/main/python/sglang/srt/models). You can learn from existing model implementations and create new files for the new models. Most models are based on the transformer architecture, making them very similar.
Another valuable resource is the [vLLM Models Directory](https://github.com/vllm-project/vllm/tree/main/vllm/model_executor/models). vLLM has extensive coverage of models, and SGLang has reused vLLM for most parts of the model implementations. This similarity makes it easy to port many models from vLLM to SGLang.
To port a model from vLLM to SGLang, you can compare these two files [SGLang LLaMA Implementation](https://github.com/sgl-project/sglang/blob/main/python/sglang/srt/models/llama2.py) and [vLLM LLaMA Implementation](https://github.com/vllm-project/vllm/blob/main/vllm/model_executor/models/llama.py). This comparison will help you understand how to convert a model implementation from vLLM to SGLang. The major difference is the replacement of PagedAttention with RadixAttention. The other parts are almost identical. Specifically,
- Replace vllm's `Attention` with `RadixAttention`.
- Replace vllm's `LogitsProcessor` with SGLang's `LogitsProcessor`.
- Remove `Sample`.
- Change `forward()` functions, and add `input_metadata`.
- Add `EntryClass` at the end.
- Test correctness by comparing the final logits and outputs of the two following commands:
- `python3 playground/reference_hf.py --model [new model]`
- `python3 -m sglang.bench_latency --model [new model] --correct --output-len 16 --trust-remote-code`
- Update [Supported Models](https://github.com/sgl-project/sglang/tree/main?tab=readme-ov-file#supported-models) at [README](../README.md).