Merge branch 'sd3' into po

README.md

@@ -9,11 +9,17 @@ __Please update PyTorch to 2.4.0. We have tested with `torch==2.4.0` and `torchv
 The command to install PyTorch is as follows:
 `pip3 install torch==2.4.0 torchvision==0.19.0 --index-url https://download.pytorch.org/whl/cu124`
 
+If you are using DeepSpeed, please install DeepSpeed with `pip install deepspeed==0.16.7`.
+
 - [FLUX.1 training](#flux1-training)
 - [SD3 training](#sd3-training)
 
 ### Recent Updates
 
+May 1, 2025:
+- The error when training FLUX.1 with mixed precision in flux_train.py with DeepSpeed enabled has been resolved. Thanks to sharlynxy for PR [#2060](https://github.com/kohya-ss/sd-scripts/pull/2060). Please refer to the PR for details.
+  - If you enable DeepSpeed, please install DeepSpeed with `pip install deepspeed==0.16.7`.
+
 Apr 27, 2025:
 - FLUX.1 training now supports CFG scale in the sample generation during training. Please use `--g` option, to specify the CFG scale (note that `--l` is used as the embedded guidance scale.) PR [#2064](https://github.com/kohya-ss/sd-scripts/pull/2064).
     - See [here](#sample-image-generation-during-training) for details.
@@ -875,6 +881,14 @@ Note: Some user reports ``ValueError: fp16 mixed precision requires a GPU`` is o
 
 (Single GPU with id `0` will be used.)
 
+## DeepSpeed installation (experimental, Linux or WSL2 only)
+  
+To install DeepSpeed, run the following command in your activated virtual environment:
+
+```bash
+pip install deepspeed==0.16.7 
+```
+
 ## Upgrade
 
 When a new release comes out you can upgrade your repo with the following command:

library/deepspeed_utils.py

@@ -5,6 +5,8 @@ from accelerate import DeepSpeedPlugin, Accelerator
 
 from .utils import setup_logging
 
+from .device_utils import get_preferred_device
+
 setup_logging()
 import logging
 
@@ -94,6 +96,7 @@ def prepare_deepspeed_plugin(args: argparse.Namespace):
     deepspeed_plugin.deepspeed_config["train_batch_size"] = (
         args.train_batch_size * args.gradient_accumulation_steps * int(os.environ["WORLD_SIZE"])
     )
+    
     deepspeed_plugin.set_mixed_precision(args.mixed_precision)
     if args.mixed_precision.lower() == "fp16":
         deepspeed_plugin.deepspeed_config["fp16"]["initial_scale_power"] = 0  # preventing overflow.
@@ -122,18 +125,56 @@ def prepare_deepspeed_model(args: argparse.Namespace, **models):
     class DeepSpeedWrapper(torch.nn.Module):
         def __init__(self, **kw_models) -> None:
             super().__init__()
+            
             self.models = torch.nn.ModuleDict()
+            
+            wrap_model_forward_with_torch_autocast = args.mixed_precision is not "no"
 
             for key, model in kw_models.items():
                 if isinstance(model, list):
                     model = torch.nn.ModuleList(model)
+                                            
+                if wrap_model_forward_with_torch_autocast:
+                    model = self.__wrap_model_with_torch_autocast(model)  
+                
                 assert isinstance(
                     model, torch.nn.Module
                 ), f"model must be an instance of torch.nn.Module, but got {key} is {type(model)}"
+
                 self.models.update(torch.nn.ModuleDict({key: model}))
 
+        def __wrap_model_with_torch_autocast(self, model):
+            if isinstance(model, torch.nn.ModuleList):
+                model = torch.nn.ModuleList([self.__wrap_model_forward_with_torch_autocast(m) for m in model])
+            else:
+                model = self.__wrap_model_forward_with_torch_autocast(model)
+            return model
+
+        def __wrap_model_forward_with_torch_autocast(self, model):
+            
+            assert hasattr(model, "forward"), f"model must have a forward method."
+
+            forward_fn = model.forward
+
+            def forward(*args, **kwargs):
+                try:
+                    device_type = model.device.type
+                except AttributeError:
+                    logger.warning(
+                            "[DeepSpeed] model.device is not available. Using get_preferred_device() "
+                            "to determine the device_type for torch.autocast()."
+                    )                    
+                    device_type = get_preferred_device().type
+
+                with torch.autocast(device_type = device_type):
+                    return forward_fn(*args, **kwargs)
+
+            model.forward = forward
+            return model
+        
         def get_models(self):
             return self.models
+        
 
     ds_model = DeepSpeedWrapper(**models)
     return ds_model

library/train_util.py

@@ -1170,8 +1170,11 @@ class BaseDataset(torch.utils.data.Dataset):
                     self.bucket_info["buckets"][i] = {"resolution": reso, "count": len(bucket)}
                     logger.info(f"bucket {i}: resolution {reso}, count: {len(bucket)}")
 
-            img_ar_errors = np.array(img_ar_errors)
-            mean_img_ar_error = np.mean(np.abs(img_ar_errors))
+            if len(img_ar_errors) == 0:
+                mean_img_ar_error = 0  # avoid NaN
+            else:
+                img_ar_errors = np.array(img_ar_errors)
+                mean_img_ar_error = np.mean(np.abs(img_ar_errors))
             self.bucket_info["mean_img_ar_error"] = mean_img_ar_error
             logger.info(f"mean ar error (without repeats): {mean_img_ar_error}")
 
@@ -5751,6 +5754,11 @@ def load_target_model(args, weight_dtype, accelerator, unet_use_linear_projectio
 
 
 def patch_accelerator_for_fp16_training(accelerator):
+    
+    from accelerate import DistributedType
+    if accelerator.distributed_type == DistributedType.DEEPSPEED:
+        return
+    
     org_unscale_grads = accelerator.scaler._unscale_grads_
 
     def _unscale_grads_replacer(optimizer, inv_scale, found_inf, allow_fp16):

networks/lora_flux.py

@@ -955,26 +955,26 @@ class LoRANetwork(torch.nn.Module):
         for lora in self.text_encoder_loras + self.unet_loras:
             lora.update_grad_norms()
 
-    def grad_norms(self) -> Tensor:
+    def grad_norms(self) -> Tensor | None:
         grad_norms = []
         for lora in self.text_encoder_loras + self.unet_loras:
             if hasattr(lora, "grad_norms") and lora.grad_norms is not None:
                 grad_norms.append(lora.grad_norms.mean(dim=0))
-        return torch.stack(grad_norms) if len(grad_norms) > 0 else torch.tensor([])
+        return torch.stack(grad_norms) if len(grad_norms) > 0 else None
 
-    def weight_norms(self) -> Tensor:
+    def weight_norms(self) -> Tensor | None:
         weight_norms = []
         for lora in self.text_encoder_loras + self.unet_loras:
             if hasattr(lora, "weight_norms") and lora.weight_norms is not None:
                 weight_norms.append(lora.weight_norms.mean(dim=0))
-        return torch.stack(weight_norms) if len(weight_norms) > 0 else torch.tensor([])
+        return torch.stack(weight_norms) if len(weight_norms) > 0 else None
 
-    def combined_weight_norms(self) -> Tensor:
+    def combined_weight_norms(self) -> Tensor | None:
         combined_weight_norms = []
         for lora in self.text_encoder_loras + self.unet_loras:
             if hasattr(lora, "combined_weight_norms") and lora.combined_weight_norms is not None:
                 combined_weight_norms.append(lora.combined_weight_norms.mean(dim=0))
-        return torch.stack(combined_weight_norms) if len(combined_weight_norms) > 0 else torch.tensor([])
+        return torch.stack(combined_weight_norms) if len(combined_weight_norms) > 0 else None
 
 
     def load_weights(self, file):