3 files changed, 54 insertions, 43 deletions

diff --git a/training/functional.py b/training/functional.py
index 1b6162b..c6b4dc3 100644
--- a/training/functional.py
+++ b/training/functional.py
@@ -73,7 +73,7 @@ def save_samples(
     vae: AutoencoderKL,
     sample_scheduler: DPMSolverMultistepScheduler,
     train_dataloader: DataLoader,
-    val_dataloader: DataLoader,
+    val_dataloader: Optional[DataLoader],
     dtype: torch.dtype,
     output_dir: Path,
     seed: int,
@@ -111,11 +111,13 @@ def save_samples(
 
     generator = torch.Generator(device=accelerator.device).manual_seed(seed)
 
-    for pool, data, gen in [
-        ("stable", val_dataloader, generator),
-        ("val", val_dataloader, None),
-        ("train", train_dataloader, None)
-    ]:
+    datasets: list[tuple[str, DataLoader, Optional[torch.Generator]]] = [("train", train_dataloader, None)]
+
+    if val_dataloader is not None:
+        datasets.append(("stable", val_dataloader, generator))
+        datasets.append(("val", val_dataloader, None))
+
+    for pool, data, gen in datasets:
         all_samples = []
         file_path = samples_path.joinpath(pool, f"step_{step}.jpg")
         file_path.parent.mkdir(parents=True, exist_ok=True)
@@ -328,7 +330,7 @@ def train_loop(
     optimizer: torch.optim.Optimizer,
     lr_scheduler: torch.optim.lr_scheduler._LRScheduler,
     train_dataloader: DataLoader,
-    val_dataloader: DataLoader,
+    val_dataloader: Optional[DataLoader],
     loss_step: Union[Callable[[int, Any], Tuple[Any, Any, int]], Callable[[int, Any, bool], Tuple[Any, Any, int]]],
     sample_frequency: int = 10,
     checkpoint_frequency: int = 50,
@@ -337,7 +339,7 @@ def train_loop(
     callbacks: TrainingCallbacks = TrainingCallbacks(),
 ):
     num_training_steps_per_epoch = math.ceil(len(train_dataloader) / accelerator.gradient_accumulation_steps)
-    num_val_steps_per_epoch = len(val_dataloader)
+    num_val_steps_per_epoch = len(val_dataloader) if val_dataloader is not None else 0
 
     num_training_steps = num_training_steps_per_epoch * num_epochs
     num_val_steps = num_val_steps_per_epoch * num_epochs
@@ -350,6 +352,7 @@ def train_loop(
     avg_loss_val = AverageMeter()
     avg_acc_val = AverageMeter()
 
+    max_acc = 0.0
     max_acc_val = 0.0
 
     local_progress_bar = tqdm(
@@ -432,49 +435,57 @@ def train_loop(
 
             accelerator.wait_for_everyone()
 
-            model.eval()
+            if val_dataloader is not None:
+                model.eval()
 
-            cur_loss_val = AverageMeter()
-            cur_acc_val = AverageMeter()
+                cur_loss_val = AverageMeter()
+                cur_acc_val = AverageMeter()
 
-            with torch.inference_mode(), on_eval():
-                for step, batch in enumerate(val_dataloader):
-                    loss, acc, bsz = loss_step(step, batch, True)
+                with torch.inference_mode(), on_eval():
+                    for step, batch in enumerate(val_dataloader):
+                        loss, acc, bsz = loss_step(step, batch, True)
 
-                    loss = loss.detach_()
-                    acc = acc.detach_()
+                        loss = loss.detach_()
+                        acc = acc.detach_()
 
-                    cur_loss_val.update(loss, bsz)
-                    cur_acc_val.update(acc, bsz)
+                        cur_loss_val.update(loss, bsz)
+                        cur_acc_val.update(acc, bsz)
 
-                    avg_loss_val.update(loss, bsz)
-                    avg_acc_val.update(acc, bsz)
+                        avg_loss_val.update(loss, bsz)
+                        avg_acc_val.update(acc, bsz)
 
-                    local_progress_bar.update(1)
-                    global_progress_bar.update(1)
+                        local_progress_bar.update(1)
+                        global_progress_bar.update(1)
 
-                    logs = {
-                        "val/loss": avg_loss_val.avg.item(),
-                        "val/acc": avg_acc_val.avg.item(),
-                        "val/cur_loss": loss.item(),
-                        "val/cur_acc": acc.item(),
-                    }
-                    local_progress_bar.set_postfix(**logs)
+                        logs = {
+                            "val/loss": avg_loss_val.avg.item(),
+                            "val/acc": avg_acc_val.avg.item(),
+                            "val/cur_loss": loss.item(),
+                            "val/cur_acc": acc.item(),
+                        }
+                        local_progress_bar.set_postfix(**logs)
 
-            logs["val/cur_loss"] = cur_loss_val.avg.item()
-            logs["val/cur_acc"] = cur_acc_val.avg.item()
+                logs["val/cur_loss"] = cur_loss_val.avg.item()
+                logs["val/cur_acc"] = cur_acc_val.avg.item()
 
-            accelerator.log(logs, step=global_step)
+                accelerator.log(logs, step=global_step)
 
-            local_progress_bar.clear()
-            global_progress_bar.clear()
+                local_progress_bar.clear()
+                global_progress_bar.clear()
 
-            if accelerator.is_main_process:
-                if avg_acc_val.avg.item() > max_acc_val:
-                    accelerator.print(
-                        f"Global step {global_step}: Validation accuracy reached new maximum: {max_acc_val:.2e} -> {avg_acc_val.avg.item():.2e}")
-                    on_checkpoint(global_step + global_step_offset, "milestone")
-                    max_acc_val = avg_acc_val.avg.item()
+                if accelerator.is_main_process:
+                    if avg_acc_val.avg.item() > max_acc_val:
+                        accelerator.print(
+                            f"Global step {global_step}: Validation accuracy reached new maximum: {max_acc_val:.2e} -> {avg_acc_val.avg.item():.2e}")
+                        on_checkpoint(global_step + global_step_offset, "milestone")
+                        max_acc_val = avg_acc_val.avg.item()
+            else:
+                if accelerator.is_main_process:
+                    if avg_acc.avg.item() > max_acc:
+                        accelerator.print(
+                            f"Global step {global_step}: Training accuracy reached new maximum: {max_acc:.2e} -> {avg_acc.avg.item():.2e}")
+                        on_checkpoint(global_step + global_step_offset, "milestone")
+                        max_acc = avg_acc.avg.item()
 
         # Create the pipeline using using the trained modules and save it.
         if accelerator.is_main_process:
@@ -499,7 +510,7 @@ def train(
     seed: int,
     project: str,
     train_dataloader: DataLoader,
-    val_dataloader: DataLoader,
+    val_dataloader: Optional[DataLoader],
     optimizer: torch.optim.Optimizer,
     lr_scheduler: torch.optim.lr_scheduler._LRScheduler,
     callbacks_fn: Callable[..., TrainingCallbacks],
diff --git a/training/strategy/dreambooth.py b/training/strategy/dreambooth.py
index 6e7ebe2..aeaa828 100644
--- a/training/strategy/dreambooth.py
+++ b/training/strategy/dreambooth.py
@@ -26,7 +26,7 @@ def dreambooth_strategy(
     vae: AutoencoderKL,
     sample_scheduler: DPMSolverMultistepScheduler,
     train_dataloader: DataLoader,
-    val_dataloader: DataLoader,
+    val_dataloader: Optional[DataLoader],
     output_dir: Path,
     seed: int,
     train_text_encoder_epochs: int,
diff --git a/training/strategy/ti.py b/training/strategy/ti.py
index 753dce0..568f9eb 100644
--- a/training/strategy/ti.py
+++ b/training/strategy/ti.py
@@ -26,7 +26,7 @@ def textual_inversion_strategy(
     vae: AutoencoderKL,
     sample_scheduler: DPMSolverMultistepScheduler,
     train_dataloader: DataLoader,
-    val_dataloader: DataLoader,
+    val_dataloader: Optional[DataLoader],
     output_dir: Path,
     seed: int,
     placeholder_tokens: list[str],