[v1] fix padding free with sp (#10513)

examples/v1/train_batching_strategy/train_full_fsdp2_dynamic_padding_free.yaml

@@ -0,0 +1,30 @@
+model: Qwen/Qwen3-0.6B
+model_class: llm
+
+template: qwen3_nothink
+
+kernel_config:
+  name: auto
+  include_kernels: auto # choice: null/true/false/auto/kernel_id1,kernel_id2,kernel_id3, default is null
+
+quant_config: null
+
+dist_config:
+  name: fsdp2
+  dcp_path: null # /mnt/f/pretrain_models/Qwen3-0.6B-dcp
+
+### data
+train_dataset: data/v1_sft_demo.yaml
+
+### training
+output_dir: outputs/test_fsdp2
+micro_batch_size: 4
+batching_strategy: dynamic_padding_free
+flash_attn: flash_attention2
+cutoff_len: 2048
+learning_rate: 1.0e-4
+max_steps: 10
+
+### sample
+sample_backend: hf
+max_new_tokens: 128

examples/v1/train_batching_strategy/train_full_fsdp2_padding_free.yaml

@@ -20,7 +20,7 @@ train_dataset: data/v1_sft_demo.yaml
 output_dir: outputs/test_fsdp2
 micro_batch_size: 4
 batching_strategy: padding_free
-flash_attn: fa2
+flash_attn: flash_attention2
 cutoff_len: 2048
 learning_rate: 1.0e-4
 max_steps: 10

src/llamafactory/v1/config/arg_parser.py

@@ -57,15 +57,12 @@ def get_args(args: InputArgument = None) -> tuple[ModelArguments, DataArguments,
             print(f"Got unknown args, potentially deprecated arguments: {unknown_args}")
             raise ValueError(f"Some specified arguments are not used by the HfArgumentParser: {unknown_args}")
 
+    model_args, data_args, training_args, sample_args = parsed_args
     # Seed as early as possible after argument parsing so all downstream
     # components (dist init, dataloader, model init in run_* entrypoints) share the same RNG state.
-    for arg in parsed_args:
+    set_seed(training_args.seed, full_determinism=training_args.full_determinism)
-        seed = getattr(arg, "seed", None)
-        if seed is not None:
-            set_seed(seed)
-            break
 
-    return tuple(parsed_args)
+    return model_args, data_args, training_args, sample_args
 
 
 if __name__ == "__main__":

src/llamafactory/v1/config/training_args.py

@@ -85,6 +85,10 @@ class TrainingArguments:
         default=42,
         metadata={"help": "Random seed that will be set at the beginning of training."},
     )
+    full_determinism: bool = field(
+        default=False,
+        metadata={"help": "Enable full deterministic mode for reproducible distributed training."},
+    )
     resume_from_checkpoint: str | None = field(
         default=None,
         metadata={"help": "Path to a checkpoint directory to resume training from, or 'auto' to find the latest."},

src/llamafactory/v1/plugins/model_plugins/parallelization/ulysses.py

@@ -114,7 +114,6 @@ class UlyssesAttention(torch.nn.Module):
         # TODO (Reza): change the api on the megatron-deepspeed side so that we only receive all data (q,k, and v) together!
         # in shape : e.g.,  [s/p:h:]
         # (bs, seq_len/N, head_cnt, head_size) -> (bs, seq_len, head_cnt/N, head_size)
-
         # scatter 2, gather 1
         q = SeqAllToAll4D.apply(self.spg, query, self.scatter_idx, self.gather_idx)
         k = SeqAllToAll4D.apply(self.spg, key, self.scatter_idx, self.gather_idx)
@@ -123,10 +122,15 @@ class UlyssesAttention(torch.nn.Module):
         if softmax_scale is None:
             softmax_scale = q.shape[-1] ** -0.5
 
-        if attention_mask is None:
         if position_ids is not None:
-                attention_mask = torch.ones_like(position_ids).to(torch.int64)
+            global_position_ids = [
+                torch.empty_like(position_ids) for _ in range(get_ulysses_sequence_parallel_world_size(self.spg))
+            ]
+            dist.all_gather(global_position_ids, position_ids, group=self.spg)
+            position_ids = torch.cat(global_position_ids, dim=-1).contiguous()
+            attention_mask = None
         else:
+            if attention_mask is None:
                 attention_mask = torch.ones(q.shape[0], q.shape[1], dtype=torch.int64, device=q.device)
             else:
                 attention_mask = attention_mask.to(torch.int64)

src/llamafactory/v1/utils/helper.py

@@ -13,21 +13,45 @@
 # limitations under the License.
 
 
+import random
+
+import numpy as np
 import torch
 from transformers import PreTrainedTokenizer
 from transformers import set_seed as hf_set_seed
 
+from ..accelerator.helper import is_torch_npu_available
 from ..accelerator.interface import DistributedInterface
 from .constants import IGNORE_INDEX
 from .types import BatchInput, ModelInput, Processor, Tensor
 
 
-def set_seed(seed: int) -> None:
+def enable_full_determinism(seed: int) -> None:
+    """Enable full deterministic mode for reproducible distributed training."""
+    random.seed(seed)
+    np.random.seed(seed)
+    torch.manual_seed(seed)
+    torch.cuda.manual_seed(seed)
+    torch.cuda.manual_seed_all(seed)
+    torch.use_deterministic_algorithms(True, warn_only=True)
+    torch.backends.cudnn.deterministic = True
+    torch.backends.cudnn.benchmark = False
+    torch.backends.cudnn.enabled = False
+    if is_torch_npu_available():
+        torch.npu.manual_seed(seed)
+        torch.npu.manual_seed_all(seed)
+
+
+def set_seed(seed: int, full_determinism: bool = False) -> None:
     """Set seed for reproducibility.
 
     Args:
         seed: Random seed.
+        full_determinism: Whether to enable full deterministic mode.
     """
+    if full_determinism:
+        enable_full_determinism(seed)
+    else:
         hf_set_seed(seed)