docs : 拆分文档并补充类图缺失类和关系线
- 将 design.md 拆分为 architecture.md / inference.md / training.md - 精简 dataflow.md 为纯数据管道 - 删除 design.md 和 introduction.md - 更新 README.md 和 README-zh-CN.md 链接 - 补充 ChatMessage / AnthropicMessage 等 6 条孤立类关系线 - 补充 BaseModelConfig 和 TaskManager 两个缺失类
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# Inference
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## KV Cache
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At decode time, only the last query token matters. All previous K/V are cached to avoid recomputation:
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$$
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o_n = \sum_j \text{softmax}\left(\frac{q_n k_j}{\sqrt{d_k}}\right) v_j
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$$
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RoPE is applied **before** KV cache write, not after — otherwise position encoding drift occurs.
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## KVCache System
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Six classes working together:
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```
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KVCache (facade)
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├── Allocator bitmask-based page allocator + ref-count + LRU eviction
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├── PrefixCache hash-based prefix matching (page_hash via rolling hash)
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├── PagePool orchestrates Allocator + PrefixCache
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├── TaskTable maps task_id → page_table + cached token count
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├── Storage k_cache / v_cache tensors (n_layers × n_pages × page_size × n_kv_heads × head_dim)
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└── KvcacheView bundles Storage + page_table + total_len for attention layers
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```
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`KVCache.bind(page_table, total_len)` returns a `KvcacheView` used by attention layers via `write()` / `gather()`.
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## Continuous Batching
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`InferenceScheduler` runs a daemon thread with a 4-phase loop:
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```
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1. Cleanup → Remove finished tasks, free KV pages
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2. Refill → Pop from waiting_queue, task_alloc pages, activate
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3. Prefill → Group by (prompt_len, start_pos), run full forward
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4. Decode → Pick largest same-position group, single-token forward
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```
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## Sampling (Strategy Pattern)
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```
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BaseSamplingStrategy → TemperatureStrategy → TopKStrategy → TopPStrategy
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```
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`SamplingPipeline` composes them: Temperature → Top-K → Top-P → softmax → multinomial.
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`sample()` is a convenience shortcut for one-shot usage.
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## Protocol Handlers (Template Method)
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```python
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class ProtocolHandler(ABC):
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def handle(self):
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ctx = StreamContext(...)
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agen = engine.generate_async(prompt, ...)
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if stream: self._handle_stream(agen, ctx)
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else: self._handle_non_stream(agen, ctx)
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```
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Subclass hooks: `build_prompt()`, `create_response_id()`, `format_stream_start/token/end()`, `format_non_stream_response()`.
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`OpenAIHandler` → `/v1/chat/completions`, `AnthropicHandler` → `/v1/messages`.
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## Engine & GenerateResult
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```
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InferenceEngine
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├── generate(prompt, stream, ...) → str | List[str] | Generator
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├── generate_with_request(req) → same
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└── generate_async(prompt, ...) → AsyncGenerator
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```
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`GenerateResult` uses `Condition` for non-streaming (`wait_completion()`) and `Event` for streaming (`wait()`). Stream callback is `cb(token)`.
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## HTTP API
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```
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POST /v1/chat/completions OpenAI
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POST /v1/messages Anthropic
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GET /health {"status":"ok","model_loaded":true}
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GET /stats scheduler statistics
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```
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### OpenAI
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```bash
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curl -X POST http://localhost:8000/v1/chat/completions \
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-H "Content-Type: application/json" \
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-d '{"messages":[{"role":"user","content":"Hello"}],"max_tokens":512}'
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```
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Response:
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```json
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{
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"id": "chatcmpl-abc123",
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"object": "chat.completion",
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"choices": [{"message": {"role": "assistant", "content": "Hello!"}, "finish_reason": "stop"}],
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"usage": {"prompt_tokens": 5, "completion_tokens": 10, "total_tokens": 15}
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}
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```
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Streaming SSE: `data: {"choices":[{"delta":{"role":"assistant"}}]}` → token chunks → `data: [DONE]`
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### Anthropic
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```bash
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curl -X POST http://localhost:8000/v1/messages \
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-H "Content-Type: application/json" \
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-d '{"model":"astrai","system":"You are helpful.","messages":[{"role":"user","content":"Hello"}],"max_tokens":512}'
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```
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Supports `stop_sequences` and streaming via `event: content_block_delta`.
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### GenerationRequest Parameters
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| Param | Type | Default | Description |
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|-------|------|---------|-------------|
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| `messages` | List[dict] | required | Chat messages (role, content) |
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| `temperature` | float | 1.0 | Sampling temperature (0.0–2.0) |
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| `top_p` | float | 1.0 | Nucleus threshold |
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| `top_k` | int | 50 | Top-k count |
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| `max_tokens` | int | None | Max generation length |
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| `stream` | bool | False | Stream output |
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## Engine API
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```python
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# Non-streaming
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engine.generate("Hello", stream=False) # -> str
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engine.generate(["A", "B"], stream=False) # -> List[str]
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# Streaming
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engine.generate("Hello", stream=True) # -> Generator[str]
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engine.generate(["A", "B"], stream=True) # -> Generator[Tuple[int, str]]
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# Async
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await engine.generate_async("Hello", ...) # -> AsyncGenerator[str]
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```
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> Document Update Time: 2026-05-15
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