From 44eeba07b2e0315e2e257bc3da04935f0254b45f Mon Sep 17 00:00:00 2001 From: Linoy Tsaban <57615435+linoytsaban@users.noreply.github.com> Date: Mon, 21 Apr 2025 10:08:45 +0300 Subject: [PATCH] [Flux LoRAs] fix lr scheduler bug in distributed scenarios (#11242) * add fix * add fix * Apply style fixes --------- Co-authored-by: github-actions[bot] --- .../train_dreambooth_lora_flux_advanced.py | 26 +++++++++++++------ examples/dreambooth/train_dreambooth_flux.py | 25 +++++++++++++----- .../dreambooth/train_dreambooth_lora_flux.py | 25 +++++++++++++----- 3 files changed, 54 insertions(+), 22 deletions(-) diff --git a/examples/advanced_diffusion_training/train_dreambooth_lora_flux_advanced.py b/examples/advanced_diffusion_training/train_dreambooth_lora_flux_advanced.py index d3c60d47d0..b756fba7d6 100644 --- a/examples/advanced_diffusion_training/train_dreambooth_lora_flux_advanced.py +++ b/examples/advanced_diffusion_training/train_dreambooth_lora_flux_advanced.py @@ -1915,17 +1915,22 @@ def main(args): free_memory() # Scheduler and math around the number of training steps. - overrode_max_train_steps = False - num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) + # Check the PR https://github.com/huggingface/diffusers/pull/8312 for detailed explanation. + num_warmup_steps_for_scheduler = args.lr_warmup_steps * accelerator.num_processes if args.max_train_steps is None: - args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch - overrode_max_train_steps = True + len_train_dataloader_after_sharding = math.ceil(len(train_dataloader) / accelerator.num_processes) + num_update_steps_per_epoch = math.ceil(len_train_dataloader_after_sharding / args.gradient_accumulation_steps) + num_training_steps_for_scheduler = ( + args.num_train_epochs * accelerator.num_processes * num_update_steps_per_epoch + ) + else: + num_training_steps_for_scheduler = args.max_train_steps * accelerator.num_processes lr_scheduler = get_scheduler( args.lr_scheduler, optimizer=optimizer, - num_warmup_steps=args.lr_warmup_steps * accelerator.num_processes, - num_training_steps=args.max_train_steps * accelerator.num_processes, + num_warmup_steps=num_warmup_steps_for_scheduler, + num_training_steps=num_training_steps_for_scheduler, num_cycles=args.lr_num_cycles, power=args.lr_power, ) @@ -1949,7 +1954,6 @@ def main(args): lr_scheduler, ) else: - print("I SHOULD BE HERE") transformer, text_encoder_one, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( transformer, text_encoder_one, optimizer, train_dataloader, lr_scheduler ) @@ -1961,8 +1965,14 @@ def main(args): # We need to recalculate our total training steps as the size of the training dataloader may have changed. num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) - if overrode_max_train_steps: + if args.max_train_steps is None: args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch + if num_training_steps_for_scheduler != args.max_train_steps: + logger.warning( + f"The length of the 'train_dataloader' after 'accelerator.prepare' ({len(train_dataloader)}) does not match " + f"the expected length ({len_train_dataloader_after_sharding}) when the learning rate scheduler was created. " + f"This inconsistency may result in the learning rate scheduler not functioning properly." + ) # Afterwards we recalculate our number of training epochs args.num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch) diff --git a/examples/dreambooth/train_dreambooth_flux.py b/examples/dreambooth/train_dreambooth_flux.py index 53787e4c01..fcc1737e65 100644 --- a/examples/dreambooth/train_dreambooth_flux.py +++ b/examples/dreambooth/train_dreambooth_flux.py @@ -1407,17 +1407,22 @@ def main(args): tokens_two = torch.cat([tokens_two, class_tokens_two], dim=0) # Scheduler and math around the number of training steps. - overrode_max_train_steps = False - num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) + # Check the PR https://github.com/huggingface/diffusers/pull/8312 for detailed explanation. + num_warmup_steps_for_scheduler = args.lr_warmup_steps * accelerator.num_processes if args.max_train_steps is None: - args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch - overrode_max_train_steps = True + len_train_dataloader_after_sharding = math.ceil(len(train_dataloader) / accelerator.num_processes) + num_update_steps_per_epoch = math.ceil(len_train_dataloader_after_sharding / args.gradient_accumulation_steps) + num_training_steps_for_scheduler = ( + args.num_train_epochs * accelerator.num_processes * num_update_steps_per_epoch + ) + else: + num_training_steps_for_scheduler = args.max_train_steps * accelerator.num_processes lr_scheduler = get_scheduler( args.lr_scheduler, optimizer=optimizer, - num_warmup_steps=args.lr_warmup_steps * accelerator.num_processes, - num_training_steps=args.max_train_steps * accelerator.num_processes, + num_warmup_steps=num_warmup_steps_for_scheduler, + num_training_steps=num_training_steps_for_scheduler, num_cycles=args.lr_num_cycles, power=args.lr_power, ) @@ -1444,8 +1449,14 @@ def main(args): # We need to recalculate our total training steps as the size of the training dataloader may have changed. num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) - if overrode_max_train_steps: + if args.max_train_steps is None: args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch + if num_training_steps_for_scheduler != args.max_train_steps: + logger.warning( + f"The length of the 'train_dataloader' after 'accelerator.prepare' ({len(train_dataloader)}) does not match " + f"the expected length ({len_train_dataloader_after_sharding}) when the learning rate scheduler was created. " + f"This inconsistency may result in the learning rate scheduler not functioning properly." + ) # Afterwards we recalculate our number of training epochs args.num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch) diff --git a/examples/dreambooth/train_dreambooth_lora_flux.py b/examples/dreambooth/train_dreambooth_lora_flux.py index c8b15b9345..9de4973b6f 100644 --- a/examples/dreambooth/train_dreambooth_lora_flux.py +++ b/examples/dreambooth/train_dreambooth_lora_flux.py @@ -1524,17 +1524,22 @@ def main(args): free_memory() # Scheduler and math around the number of training steps. - overrode_max_train_steps = False - num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) + # Check the PR https://github.com/huggingface/diffusers/pull/8312 for detailed explanation. + num_warmup_steps_for_scheduler = args.lr_warmup_steps * accelerator.num_processes if args.max_train_steps is None: - args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch - overrode_max_train_steps = True + len_train_dataloader_after_sharding = math.ceil(len(train_dataloader) / accelerator.num_processes) + num_update_steps_per_epoch = math.ceil(len_train_dataloader_after_sharding / args.gradient_accumulation_steps) + num_training_steps_for_scheduler = ( + args.num_train_epochs * accelerator.num_processes * num_update_steps_per_epoch + ) + else: + num_training_steps_for_scheduler = args.max_train_steps * accelerator.num_processes lr_scheduler = get_scheduler( args.lr_scheduler, optimizer=optimizer, - num_warmup_steps=args.lr_warmup_steps * accelerator.num_processes, - num_training_steps=args.max_train_steps * accelerator.num_processes, + num_warmup_steps=num_warmup_steps_for_scheduler, + num_training_steps=num_training_steps_for_scheduler, num_cycles=args.lr_num_cycles, power=args.lr_power, ) @@ -1561,8 +1566,14 @@ def main(args): # We need to recalculate our total training steps as the size of the training dataloader may have changed. num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) - if overrode_max_train_steps: + if args.max_train_steps is None: args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch + if num_training_steps_for_scheduler != args.max_train_steps: + logger.warning( + f"The length of the 'train_dataloader' after 'accelerator.prepare' ({len(train_dataloader)}) does not match " + f"the expected length ({len_train_dataloader_after_sharding}) when the learning rate scheduler was created. " + f"This inconsistency may result in the learning rate scheduler not functioning properly." + ) # Afterwards we recalculate our number of training epochs args.num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch)