docs: audit non-CUDA documentation

- Aligns CLI and strategy metric contracts
- Refreshes architecture, dataflow, preprocessing, distributed, and eval guides
- Corrects links, TOCs, defaults, and repository paths
This commit is contained in:
2026-08-02 07:39:24 +08:00
parent 020e2eff4e
commit 288ba20db1
13 changed files with 483 additions and 267 deletions
+18 -12
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@@ -41,7 +41,10 @@ RoPE embeds position into Q/K vectors via complex rotation:
$$ q_i = R_i W_q x_i, \quad k_j = R_j W_k x_j, \quad q_i^T k_j = x_i^T W_q^T R_{i-j} W_k x_j $$
`RotaryEmbedding` pre-computes `cos_table` and `sin_table` (f32, `[max_len, dim/2]`). `forward()` returns a `(cos, sin)` tuple indexed by `position_ids`. `apply_rotary_emb` applies the rotation: during training it uses torch complex multiply (autograd-compatible); during inference it auto-dispatches to a fused CUDA kernel when available.
`RotaryEmbedding` pre-computes a complex `freqs_cis` buffer. `forward()` returns
a tensor indexed by `position_ids`. `apply_rotary_emb` applies the rotation:
during training it uses torch complex multiply (autograd-compatible); during
inference it auto-dispatches to a fused CUDA kernel when available.
## Training Loop
@@ -52,8 +55,8 @@ on_train_begin
model.train()
on_epoch_begin
for batch in dataloader:
on_batch_begin
with executor.accumulate(model):
on_batch_begin
loss_output = strategy(batch)
context.loss = loss_output["loss"].item()
context.metrics = loss_output["metrics"]
@@ -67,6 +70,7 @@ on_train_begin
if executor.sync_gradients:
on_optimizer_step
optimizer.step()
strategy.on_optimizer_step()
optimizer.zero_grad()
if scheduler:
scheduler.step()
@@ -78,16 +82,16 @@ on_train_end
| Hook | Fires | Default callback |
|------|-------|-----------------|
| `on_train_begin` | Before training starts | `GradientCheckpointingCallback` |
| `on_train_begin` | Before training starts | `GradientCheckpointingCallback`, `CheckpointCallback`, `MetricCallback` |
| `on_epoch_begin` | Start of each epoch | `ProgressBarCallback` |
| `on_batch_begin` | Every batch | — |
| `on_optimizer_step` | Every accumulation window | `GradientClippingCallback`, `MetricCallback`, `ProgressBarCallback` |
| `on_optimizer_step` | Every accumulation window | `MetricCallback`, `ProgressBarCallback`, `GradientClippingCallback` |
| `on_batch_end` | Every batch | `CheckpointCallback` |
| `on_epoch_end` | End of each epoch | `MetricCallback`, `ProgressBarCallback` |
| `on_error` | On exception during training | `CheckpointCallback`, `MetricCallback` |
| `on_train_end` | Training ends (always via finally) | `CheckpointCallback`, `MetricCallback`, `GradientCheckpointingCallback` |
| `on_train_end` | Training exits after `on_train_begin` completes (via `finally`) | `GradientCheckpointingCallback`, `CheckpointCallback`, `MetricCallback` |
Default callbacks (in order): `gradient_checkpointing` (activation checkpointing, optional), `checkpoint` (safetensors, rank-0), `metric` (JSONL + validation, rank-0), `progress_bar` (tqdm), `gradient_clipping` (always registered; computes grad norm, clips only when `max_grad_norm` is not `None`).
Default callbacks (in order): `gradient_checkpointing` (activation checkpointing, optional), `checkpoint` (safetensors, rank-0), `metric` (JSONL + validation, rank-0), `progress_bar` (tqdm, rank-0), `gradient_clipping`. The gradient-clipping callback is always registered and always calls `executor.clip_grad_norm()` with the numeric `max_grad_norm` value.
Strategies return `{"loss": Tensor, "metrics": Dict[str, float]}` when called by the trainer. Built-in metrics include the task-specific loss and, for MoE models, `moe_aux_loss` plus `moe_aux_loss_weighted`. Direct `compute_loss(batch)` calls continue to return a single loss tensor.
@@ -98,7 +102,7 @@ Strategies return `{"loss": Tensor, "metrics": Dict[str, float]}` when called by
Next-token cross-entropy with optional label smoothing:
$$
L_{\text{PT}} = -\sum_{t=1}^{T} \log P(x_t \mid x_{\lt t}; \theta)
L_{\text{PT}} = -\frac{1}{T}\sum_{t=1}^{T} \log P(x_t \mid x_{\lt t}; \theta)
$$
Keys: `input_ids`, `target_ids`. Optional: `label_smoothing`.
@@ -108,7 +112,7 @@ Keys: `input_ids`, `target_ids`. Optional: `label_smoothing`.
Masked cross-entropy (`ignore_index=-100`) over response tokens:
$$
L_{\text{SFT}} = -\sum_{t=P+1}^{P+L} \log P(s_t \mid s_{\lt t}; \theta)
L_{\text{SFT}} = -\frac{1}{L}\sum_{t=P+1}^{P+L} \log P(s_t \mid s_{\lt t}; \theta)
$$
Keys: `input_ids`, `target_ids`, `loss_mask`, `position_ids`. Optional: `label_smoothing`.
@@ -168,9 +172,9 @@ model factory.
|------|-------|-------------|
| Cosine | `CosineScheduler` | Linear warmup → cosine decay to `min_rate` |
| SGDR | `SGDRScheduler` | Cosine annealing with warm restarts (`t_mult=2`) |
| WSD | `WSDScheduler` | Warmup-Stable-Decay with sqrt cooldown |
| WSD | `WSDScheduler` | Warmup-Stable-Decay with quadratic decay |
Created by `SchedulerFactory.create(schedule_type, optimizer, **kwargs)`. Valid types: `"cosine"`, `"sgdr"`, `"wsd"`. Omit to use no scheduler.
Created by `SchedulerFactory.create(schedule_type, optimizer, **kwargs)`. Valid types: `"cosine"`, `"sgdr"`, `"wsd"`. The training CLI always creates a scheduler and defaults `--schedule_type` to `"cosine"`.
## Gradient Checkpointing
@@ -188,10 +192,12 @@ Callback wraps each `DecoderBlock.forward` with `torch.utils.checkpoint.checkpoi
```
Checkpoint(state_dict, epoch, consumed_samples, extra, meta, config)
├── save(save_dir) rank-0 only: meta.json (epoch/consumed_samples/timestamp) + config.json (model config) + model.safetensors + optional {key}.pt (optimizer.pt, scheduler.pt)
├── save(save_dir) meta.json (epoch/consumed_samples/timestamp) + config.json (model config) + model.safetensors + optional {key}.pt (optimizer.pt, scheduler.pt)
└── load(save_dir, broadcast=False) loads from local disk; set broadcast=True to broadcast metadata from rank-0
```
`Checkpoint.save()` writes whenever it is called. During training, `CheckpointCallback` uses the executor checkpoint context so only rank 0 receives a state dict and calls `save()`.
Optimizer/scheduler state persisted by default via `Checkpoint.extra`.
Model config (`context.model_config`) saved into `config.json` during training via `CheckpointCallback`.
@@ -235,4 +241,4 @@ nohup python scripts/tools/train.py \
Full parameter reference at [params.md](params.md).
> Document Update Time: 2026-07-31
> Document Update Time: 2026-08-02