# Copyright (c) 2022, NVIDIA CORPORATION. All rights reserved. """Pretrain utilities.""" import argparse from datetime import datetime import math import sys import time from typing import Callable # The earliest we can measure the start time. _TRAIN_START_TIME = time.time() import torch from torch.nn.parallel.distributed import DistributedDataParallel as torchDDP import megatron from megatron import get_args from megatron import get_signal_handler from megatron import get_timers from megatron import get_counters from megatron import get_tensorboard_writer from megatron import get_current_global_batch_size from megatron import get_num_microbatches from megatron import is_last_rank from megatron import update_num_microbatches from megatron.core import mpu, tensor_parallel from megatron import print_rank_0 from megatron import print_rank_last from megatron import print_all_nodes from megatron.checkpointing import load_checkpoint from megatron.checkpointing import save_checkpoint from megatron.model import Float16Module from megatron.model import ModelType from megatron.model import GPTModel from megatron.optimizer import get_megatron_optimizer import megatron.initialize from megatron.optimizer_param_scheduler import OptimizerParamScheduler from megatron.model import DistributedDataParallel as LocalDDP import megatron.utils from megatron.utils import unwrap_model from megatron.data.data_samplers import build_pretraining_data_loader from megatron.utils import calc_params_l2_norm from megatron.schedules import get_forward_backward_func from megatron.utils import report_memory def print_datetime(string): """Note that this call will sync across all ranks.""" torch.distributed.barrier() time_str = datetime.now().strftime('%Y-%m-%d %H:%M:%S') print_rank_0('[' + string + '] datetime: {} '.format(time_str)) def pretrain(args, train_valid_test_dataset_provider, model_provider_func, model_type: ModelType, forward_step_func, process_non_loss_data_func=None, collate_fn=None): """Main training program. This function will run the followings in the order provided: 1) initialize Megatron. 2) setup model, optimizer and lr schedule using the model_provider_func. 3) call train_val_test_data_provider to get train/val/test datasets. 4) train the modle using the forward_step_func. Arguments: train_valid_test_dataset_provider: a function that takes the size of train/valid/test dataset and returns `train, valid, test` datasets. model_provider_func: a function that returns a vanilla version of the model. By vanilla we mean a simple model on cpu with no fp16 or ddp. model_type: an enum that specifies the type of model being trained. forward_step_func: a function that takes a `data iterator` and `model`, and returns a `loss` scalar with a dictionary with key:values being the info we would like to monitor during training, for example `lm-loss: value`. We also require that this function add `batch generator` to the timers class. process_non_loss_data_func: a function to post process outputs of the network. It can be used for dumping output tensors (e.g images) to tensorboard. It takes `collected data`(list of tensors), `current iteration index` and `tensorboard writer` as arguments. extra_args_provider: a function that takes a parser and adds arguments to it. It is used for programs to add their own arguments. args_defaults: a dictionary from argument-name to argument-value. It to set already parse arguments. """ # # Initalize and get arguments, timers, and Tensorboard writer. # Set pytorch JIT layer fusion options and warmup JIT functions. megatron.initialize.set_jit_fusion_options(args) # Adjust the startup time so it reflects the largest value. # This will be closer to what scheduler will see (outside of # image ... launches. global _TRAIN_START_TIME start_time_tensor = torch.tensor([_TRAIN_START_TIME], dtype=torch.float64, device='cuda') torch.distributed.all_reduce(start_time_tensor, op=torch.distributed.ReduceOp.MIN) _TRAIN_START_TIME = start_time_tensor.item() print_rank_0('time to initialize megatron (seconds): {:.3f}'.format(time.time() - _TRAIN_START_TIME)) print_datetime('after megatron is initialized') timers = get_timers() # Model, optimizer, and learning rate. timers('model-and-optimizer-setup', log_level=0).start(barrier=True) model, optimizer, opt_param_scheduler = _setup_model_and_optimizer( model_provider_func, model_type, args=args) timers('model-and-optimizer-setup').stop() print_datetime('after model, optimizer, and learning rate scheduler are built') # Data stuff. timers('train/valid/test-data-iterators-setup', log_level=0).start( barrier=True) if args.virtual_pipeline_model_parallel_size is not None: all_data_iterators = [ build_train_valid_test_data_iterators( train_valid_test_dataset_provider, args, collate_fn=collate_fn ) for _ in range(len(model)) ] train_data_iterator = [di[0] for di in all_data_iterators] valid_data_iterator = [di[1] for di in all_data_iterators] test_data_iterator = [di[2] for di in all_data_iterators] else: train_data_iterator, valid_data_iterator, test_data_iterator \ = build_train_valid_test_data_iterators( train_valid_test_dataset_provider, args, collate_fn=collate_fn) timers('train/valid/test-data-iterators-setup').stop() print_datetime('after dataloaders are built') # Print setup timing. print_rank_0('done with setup ...') timers.log(['model-and-optimizer-setup', 'train/valid/test-data-iterators-setup'], barrier=True) print_rank_0('training ...') iteration = 0 if args.do_train and args.train_iters > 0: iteration = _train(args, forward_step_func, model, optimizer, opt_param_scheduler, train_data_iterator, valid_data_iterator, process_non_loss_data_func) print_datetime('after training is done') if args.do_valid: prefix = 'the end of training for val data' evaluate_and_print_results(prefix, forward_step_func, valid_data_iterator, model, iteration, process_non_loss_data_func, verbose=False, args=args) if args.save and iteration != 0: save_checkpoint(iteration, model, optimizer, opt_param_scheduler) if args.do_test: # Run on test data. prefix = 'the end of training for test data' evaluate_and_print_results(prefix, forward_step_func, test_data_iterator, model, 0, process_non_loss_data_func, verbose=True, args=args) def _update_train_iters(args): # For iteration-based training, we don't need to do anything if args.train_iters: return # Constant batch size with sample-based training. if args.rampup_batch_size is None: args.train_iters = args.train_samples // args.global_batch_size else: # Sample based training with rampup batch size. iterations = 0 consumed_samples = 0 # Rampup phase. while consumed_samples <= int(args.rampup_batch_size[2]): update_num_microbatches(consumed_samples, consistency_check=False) consumed_samples += get_current_global_batch_size() iterations += 1 # Reset update_num_microbatches(0, consistency_check=False) # Constant phase # Note that we throw away any partial last batch. iterations += (args.train_samples - consumed_samples) // \ args.global_batch_size args.train_iters = iterations print_rank_0('setting training iterations to {}'.format(args.train_iters)) def get_model(model_provider_func: Callable, model_type=ModelType.encoder_or_decoder, wrap_with_ddp: bool=True, args=None): """Build the model.""" assert args is not None # Build model. if mpu.get_pipeline_model_parallel_world_size() > 1 and \ args.virtual_pipeline_model_parallel_size is not None: assert model_type != ModelType.encoder_and_decoder, \ "Interleaved schedule not supported for model with both encoder and decoder" model = [] for i in range(args.virtual_pipeline_model_parallel_size): mpu.set_virtual_pipeline_model_parallel_rank(i) # Set pre_process and post_process only after virtual rank is set. pre_process = mpu.is_pipeline_first_stage() post_process = mpu.is_pipeline_last_stage() this_model = model_provider_func( pre_process=pre_process, post_process=post_process ) this_model.model_type = model_type model.append(this_model) else: pre_process = mpu.is_pipeline_first_stage() post_process = mpu.is_pipeline_last_stage() add_encoder = True add_decoder = True if model_type == ModelType.encoder_and_decoder: if mpu.get_pipeline_model_parallel_world_size() > 1: assert args.pipeline_model_parallel_split_rank is not None, \ "Split rank needs to be specified for model with both encoder and decoder" rank = mpu.get_pipeline_model_parallel_rank() split_rank = args.pipeline_model_parallel_split_rank world_size = mpu.get_pipeline_model_parallel_world_size() pre_process = rank == 0 or rank == split_rank post_process = (rank == (split_rank - 1)) or ( rank == (world_size - 1)) add_encoder = mpu.is_pipeline_stage_before_split() add_decoder = mpu.is_pipeline_stage_after_split() model = model_provider_func( pre_process=pre_process, post_process=post_process, add_encoder=add_encoder, add_decoder=add_decoder) else: model = model_provider_func( pre_process=pre_process, post_process=post_process ) model.model_type = model_type if not isinstance(model, list): model = [model] # Disallow training and inference with Transformer Engine # for non-GPT models allow_transformer_engine = all([type(m) == GPTModel for m in model]) assert allow_transformer_engine or args.transformer_impl == 'local', \ 'Transformer Engine is only approved for GPT models' # Set tensor model parallel attributes if not set. # Only parameters that are already tensor model parallel have these # attributes set for them. We should make sure the default attributes # are set for all params so the optimizer can use them. for model_module in model: for param in model_module.parameters(): tensor_parallel.set_defaults_if_not_set_tensor_model_parallel_attributes(param) # Print number of parameters. if mpu.get_data_parallel_rank() == 0: print(' > number of parameters on (tensor, pipeline) ' 'model parallel rank ({}, {}): {}'.format( mpu.get_tensor_model_parallel_rank(), mpu.get_pipeline_model_parallel_rank(), sum([sum([p.nelement() for p in model_module.parameters()]) for model_module in model])), flush=True) # GPU allocation. for model_module in model: model_module.cuda(torch.cuda.current_device()) # Fp16 conversion. if args.fp16 or args.bf16: model = [Float16Module(model_module, args) for model_module in model] if wrap_with_ddp: if args.DDP_impl == 'torch': i = torch.cuda.current_device() model = [torchDDP(model_module, device_ids=[i], output_device=i, process_group=mpu.get_data_parallel_group()) for model_module in model] elif args.DDP_impl == 'local': model = [LocalDDP(model_module, args.accumulate_allreduce_grads_in_fp32, args.use_contiguous_buffers_in_local_ddp) for model_module in model] # broad cast params from data parallel src rank to other data parallel ranks if args.data_parallel_random_init: for model_module in model: model_module.broadcast_params() else: raise NotImplementedError('Unknown DDP implementation specified: ' '{}. Exiting.'.format(args.DDP_impl)) return model def _get_optimizer_param_scheduler(optimizer, args): """Build the learning rate scheduler.""" # Iteration-based training. if args.train_iters: if args.lr_decay_iters is None: args.lr_decay_iters = args.train_iters lr_decay_steps = args.lr_decay_iters * args.global_batch_size wd_incr_steps = args.train_iters * args.global_batch_size if args.lr_warmup_fraction is not None: lr_warmup_steps = args.lr_warmup_fraction * lr_decay_steps else: lr_warmup_steps = args.lr_warmup_iters * args.global_batch_size # Sample-based training. elif args.train_samples: # We need to set training iters for later use. Technically # we need to adjust the training samples too (due to last # batch being incomplete) but we leave it as is for now. _update_train_iters(args) if args.lr_decay_samples is None: args.lr_decay_samples = args.train_samples lr_decay_steps = args.lr_decay_samples wd_incr_steps = args.train_samples if args.lr_warmup_fraction is not None: lr_warmup_steps = args.lr_warmup_fraction * lr_decay_steps else: lr_warmup_steps = args.lr_warmup_samples else: raise Exception( 'either train_iters or train_samples should be provided.') opt_param_scheduler = OptimizerParamScheduler( optimizer, max_lr=args.lr, min_lr=args.min_lr, lr_warmup_steps=lr_warmup_steps, lr_decay_steps=lr_decay_steps, lr_decay_style=args.lr_decay_style, start_wd=args.start_weight_decay, end_wd=args.end_weight_decay, wd_incr_steps=wd_incr_steps, wd_incr_style=args.weight_decay_incr_style, use_checkpoint_opt_param_scheduler=args.use_checkpoint_opt_param_scheduler, override_opt_param_scheduler=args.override_opt_param_scheduler) return opt_param_scheduler def _setup_model_and_optimizer(model_provider_func, model_type, no_wd_decay_cond=None, scale_lr_cond=None, lr_mult=1.0, args=None): assert args is not None model = get_model(model_provider_func, model_type, args=args) unwrapped_model = unwrap_model(model, (torchDDP, LocalDDP, Float16Module)) optimizer = get_megatron_optimizer(model, no_wd_decay_cond, scale_lr_cond, lr_mult) opt_param_scheduler = _get_optimizer_param_scheduler(optimizer, args) if args.load is not None: timers = get_timers() timers('load-checkpoint', log_level=0).start(barrier=True) args.iteration = load_checkpoint(model, optimizer, opt_param_scheduler) timers('load-checkpoint').stop(barrier=True) timers.log(['load-checkpoint']) optimizer.reload_model_params() else: args.iteration = 0 # We only support local DDP with multiple micro-batches. if len(model) > 1 or mpu.get_pipeline_model_parallel_world_size() > 1: assert args.DDP_impl == 'local' # get model without FP16 and/or TorchDDP wrappers if args.iteration == 0 and len(unwrapped_model) == 1 \ and hasattr(unwrapped_model[0], 'init_state_dict_from_bert'): print_rank_0("Initializing ICT from pretrained BERT model") unwrapped_model[0].init_state_dict_from_bert() if args.fp16: optimizer.reload_model_params() return model, optimizer, opt_param_scheduler def train_step(forward_step_func, data_iterator, model, optimizer, opt_param_scheduler, iteration, args): """Single training step.""" timers = get_timers() skip_iter = iteration in args.skip_iters if skip_iter: print_all_nodes("IMPORTANT! Skipping backprop for this iteration!") # Set grad to zero. if args.DDP_impl == 'local' and args.use_contiguous_buffers_in_local_ddp: for partition in model: partition.zero_grad_buffer() optimizer.zero_grad() # Forward pass. timers('forward-backward', log_level=1).start( barrier=args.barrier_with_L1_time) forward_backward_func = get_forward_backward_func() fwd_bwd_timers = timers if args.timing_log_level > 1 else None losses_reduced = forward_backward_func( forward_step_func, data_iterator, model, optimizer, fwd_bwd_timers, forward_only=skip_iter) timers('forward-backward').stop() # Empty unused memory. if args.empty_unused_memory_level >= 1: torch.cuda.empty_cache() # Reduce gradients. if skip_iter: update_successful = False grad_norm = None num_zeros_in_grad = None else: optimizer.reduce_model_grads(args, timers) # Update parameters. timers('optimizer', log_level=1).start(barrier=args.barrier_with_L1_time) update_successful, grad_norm, num_zeros_in_grad = optimizer.step(args, timers) timers('optimizer').stop() # Gather params. if update_successful: optimizer.gather_model_params(args, timers) # Update learning rate. if update_successful: increment = get_num_microbatches() * \ args.micro_batch_size * \ args.data_parallel_size opt_param_scheduler.step(increment=increment) skipped_iter = 0 else: skipped_iter = 1 # Empty unused memory. if args.empty_unused_memory_level >= 2: torch.cuda.empty_cache() if mpu.is_pipeline_last_stage(ignore_virtual=True): # Average loss across microbatches. loss_reduced = {} for key in losses_reduced[0]: losses_reduced_for_key = [x[key] for x in losses_reduced] loss_reduced[key] = sum(losses_reduced_for_key) / len(losses_reduced_for_key) return loss_reduced, skipped_iter, grad_norm, num_zeros_in_grad return {}, skipped_iter, grad_norm, num_zeros_in_grad def training_log(loss_dict, total_loss_dict, learning_rate, iteration, loss_scale, report_memory_flag, skipped_iter, grad_norm, params_norm, num_zeros_in_grad): """Log training information such as losses, timing, ....""" args = get_args() timers = get_timers() writer = get_tensorboard_writer() # Advanced, skipped, and Nan iterations. advanced_iters_key = 'advanced iterations' skipped_iters_key = 'skipped iterations' nan_iters_key = 'nan iterations' # Advanced iterations. if not skipped_iter: total_loss_dict[advanced_iters_key] = total_loss_dict.get( advanced_iters_key, 0) + 1 else: if advanced_iters_key not in total_loss_dict: total_loss_dict[advanced_iters_key] = 0 # Skipped iterations. total_loss_dict[skipped_iters_key] = total_loss_dict.get( skipped_iters_key, 0) + skipped_iter # Update losses and set nan iterations got_nan = False for key in loss_dict: if not skipped_iter: total_loss_dict[key] = total_loss_dict.get( key, torch.cuda.FloatTensor([0.0])) + loss_dict[key] else: value = loss_dict[key].float().sum().item() is_nan = value == float('inf') or \ value == -float('inf') or \ value != value got_nan = got_nan or is_nan total_loss_dict[nan_iters_key] = total_loss_dict.get( nan_iters_key, 0) + int(got_nan) # Logging. timers_to_log = [ 'forward-backward', 'forward-compute', 'backward-compute', 'batch-generator', 'forward-recv', 'forward-send', 'backward-recv', 'backward-send', 'forward-send-forward-recv', 'forward-send-backward-recv', 'backward-send-forward-recv', 'backward-send-backward-recv', 'forward-backward-send-forward-backward-recv', 'layernorm-grads-all-reduce', 'embedding-grads-all-reduce', 'grads-all-reduce', 'grads-reduce-scatter', 'params-all-gather', 'optimizer-copy-to-main-grad', 'optimizer-unscale-and-check-inf', 'optimizer-clip-main-grad', 'optimizer-count-zeros', 'optimizer-inner-step', 'optimizer-copy-main-to-model-params', 'optimizer'] # Calculate batch size. batch_size = args.micro_batch_size * args.data_parallel_size * \ get_num_microbatches() total_iterations = total_loss_dict[advanced_iters_key] + \ total_loss_dict[skipped_iters_key] # Tensorboard values. # Timer requires all the ranks to call. if args.log_timers_to_tensorboard and \ (iteration % args.tensorboard_log_interval == 0): timers.write(timers_to_log, writer, iteration, normalizer=total_iterations) if writer and (iteration % args.tensorboard_log_interval == 0): if args.log_learning_rate_to_tensorboard: writer.add_scalar('learning_rate', learning_rate, iteration) writer.add_scalar('learning_rate vs samples', learning_rate, args.consumed_train_samples) if args.log_batch_size_to_tensorboard: writer.add_scalar('batch_size', batch_size, iteration) writer.add_scalar('batch_size vs samples', batch_size, args.consumed_train_samples) for key in loss_dict: writer.add_scalar(key, loss_dict[key], iteration) writer.add_scalar(key + ' vs samples', loss_dict[key], args.consumed_train_samples) if args.log_loss_scale_to_tensorboard: writer.add_scalar('loss_scale', loss_scale, iteration) writer.add_scalar('loss_scale vs samples', loss_scale, args.consumed_train_samples) if args.log_world_size_to_tensorboard: writer.add_scalar('world_size', args.world_size, iteration) writer.add_scalar('world_size vs samples', args.world_size, args.consumed_train_samples) if grad_norm is not None: writer.add_scalar('grad_norm', grad_norm, iteration) writer.add_scalar('grad_norm vs samples', grad_norm, args.consumed_train_samples) if num_zeros_in_grad is not None: writer.add_scalar('num_zeros', num_zeros_in_grad, iteration) writer.add_scalar('num_zeros vs samples', num_zeros_in_grad, args.consumed_train_samples) if params_norm is not None: writer.add_scalar('params_norm', params_norm, iteration) writer.add_scalar('params_norm vs samples', params_norm, args.consumed_train_samples) if args.log_memory_to_tensorboard: mem_stats = torch.cuda.memory_stats() writer.add_scalar( "mem-reserved-bytes", mem_stats["reserved_bytes.all.current"], iteration, ) writer.add_scalar( "mem-allocated-bytes", mem_stats["allocated_bytes.all.current"], iteration, ) writer.add_scalar( "mem-allocated-count", mem_stats["allocation.all.current"], iteration, ) if iteration % args.log_interval == 0: elapsed_time = timers('interval-time').elapsed(barrier=True) elapsed_time_per_iteration = elapsed_time / total_iterations counters = get_counters() tokens = counters.pop('tokens') # reset counter for future iterations tokens_per_sec = tokens/(elapsed_time) if writer: if args.log_timers_to_tensorboard: writer.add_scalar('iteration-time', elapsed_time_per_iteration, iteration) writer.add_scalar('tokens-per-sec', tokens_per_sec, iteration) log_string = ' iteration {:8d}/{:8d} |'.format( iteration, args.train_iters) log_string += ' consumed samples: {:12d} |'.format( args.consumed_train_samples) log_string += ' elapsed time per iteration (ms): {:.1f} |'.format( elapsed_time_per_iteration * 1000.0) log_string += f' rate (tokens/sec): {tokens_per_sec:.2f} |' log_string += ' learning rate: {:.3E} |'.format(learning_rate) log_string += ' global batch size: {:5d} |'.format(batch_size) for key in total_loss_dict: if key not in [advanced_iters_key, skipped_iters_key, nan_iters_key]: avg = total_loss_dict[key].item() / \ float(max(1, total_loss_dict[advanced_iters_key])) if avg > 0.0: log_string += ' {}: {:.6E} |'.format(key, avg) total_loss_dict[key] = torch.cuda.FloatTensor([0.0]) log_string += ' loss scale: {:.1f} |'.format(loss_scale) if grad_norm is not None: log_string += ' grad norm: {:.3f} |'.format(grad_norm) if num_zeros_in_grad is not None: log_string += ' num zeros: {:.1f} |'.format(num_zeros_in_grad) if params_norm is not None: log_string += ' params norm: {:.3f} |'.format(params_norm) log_string += ' number of skipped iterations: {:3d} |'.format( total_loss_dict[skipped_iters_key]) log_string += ' number of nan iterations: {:3d} |'.format( total_loss_dict[nan_iters_key]) total_loss_dict[advanced_iters_key] = 0 total_loss_dict[skipped_iters_key] = 0 total_loss_dict[nan_iters_key] = 0 print_all_nodes(log_string) if report_memory_flag and learning_rate > 0.: # Report memory after optimizer state has been initialized. report_memory('(after {} iterations)'.format(iteration)) report_memory_flag = False timers.log(timers_to_log, normalizer=args.log_interval) return report_memory_flag def save_checkpoint_and_time(iteration, model, optimizer, opt_param_scheduler): timers = get_timers() # Extra barrier is added to make sure # all ranks report the max time. timers('save-checkpoint', log_level=0).start(barrier=True) save_checkpoint(iteration, model, optimizer, opt_param_scheduler) timers('save-checkpoint').stop(barrier=True) timers.log(['save-checkpoint']) def _train(args, forward_step_func, model, optimizer, opt_param_scheduler, train_data_iterator, valid_data_iterator, process_non_loss_data_func): """Train the model function.""" timers = get_timers() # Write args to tensorboard megatron.initialize.write_args_to_tensorboard(args) # Turn on training mode which enables dropout. for model_module in model: model_module.train() # Tracking loss. total_loss_dict = {} # Iterations. iteration = args.iteration counters = get_counters() timers('interval-time', log_level=0).start(barrier=True) print_datetime('before the start of training step') report_memory_flag = True while iteration < args.train_iters: update_num_microbatches(args.consumed_train_samples) args.curr_iteration = iteration loss_dict, skipped_iter, grad_norm, num_zeros_in_grad = \ train_step(forward_step_func, train_data_iterator, model, optimizer, opt_param_scheduler, iteration, args) iteration += 1 args.consumed_train_samples += mpu.get_data_parallel_world_size() * \ args.micro_batch_size * \ get_num_microbatches() # Logging. loss_scale = optimizer.get_loss_scale().item() params_norm = None if args.log_params_norm: params_norm = calc_params_l2_norm(model) report_memory_flag = training_log(loss_dict, total_loss_dict, optimizer.param_groups[0]['lr'], iteration, loss_scale, report_memory_flag, skipped_iter, grad_norm, params_norm, num_zeros_in_grad) # Autoresume if args.adlr_autoresume and \ (iteration % args.adlr_autoresume_interval == 0): megatron.utils.check_adlr_autoresume_termination(iteration, model, optimizer, opt_param_scheduler, args) # Evaluation if args.eval_interval and iteration % args.eval_interval == 0 and \ args.do_valid: prefix = 'iteration {}'.format(iteration) current_tokens = counters['tokens'] evaluate_and_print_results(prefix, forward_step_func, valid_data_iterator, model, iteration, process_non_loss_data_func, verbose=False, args=args) counters['tokens'] = current_tokens # if using wandb writer, flush the stats of train_step & potentially evaluate writer = get_tensorboard_writer() if hasattr(writer, "flush_all"): writer.flush_all() # Checkpointing saved_checkpoint = False if args.exit_signal_handler: signal_handler = get_signal_handler() if any(signal_handler.signals_received()): save_checkpoint_and_time(iteration, model, optimizer, opt_param_scheduler) print_datetime('exiting program after receiving SIGTERM.') sys.exit() if args.save and args.save_interval and \ iteration % args.save_interval == 0: save_checkpoint_and_time(iteration, model, optimizer, opt_param_scheduler) saved_checkpoint = True # Exiting based on duration if args.exit_duration_in_mins: train_time = (time.time() - _TRAIN_START_TIME) / 60.0 done_cuda = torch.cuda.IntTensor( [train_time > args.exit_duration_in_mins]) torch.distributed.all_reduce( done_cuda, op=torch.distributed.ReduceOp.MAX) done = done_cuda.item() if done: if not saved_checkpoint: save_checkpoint_and_time(iteration, model, optimizer, opt_param_scheduler) print_datetime('exiting program after {} minutes'.format(train_time)) sys.exit() # Exiting based on iterations if args.exit_interval and iteration % args.exit_interval == 0: if not saved_checkpoint: save_checkpoint_and_time(iteration, model, optimizer, opt_param_scheduler) torch.distributed.barrier() print_datetime('exiting program at iteration {}'.format(iteration)) sys.exit() return iteration def evaluate(forward_step_func, data_iterator, model, process_non_loss_data_func, verbose=False): """Evaluation.""" args = get_args() # Turn on evaluation mode which disables dropout. for model_module in model: model_module.eval() total_loss_dict = {} with torch.no_grad(): iteration = 0 while iteration < args.eval_iters: iteration += 1 if verbose and iteration % args.log_interval == 0: print_rank_0('Evaluating iter {}/{}'.format(iteration, args.eval_iters)) forward_backward_func = get_forward_backward_func() loss_dicts = forward_backward_func( forward_step_func, data_iterator, model, optimizer=None, timers=None, forward_only=True) # Empty unused memory if args.empty_unused_memory_level >= 1: torch.cuda.empty_cache() if mpu.is_pipeline_last_stage(ignore_virtual=True): # Reduce across processes. for loss_dict in loss_dicts: for key in loss_dict: total_loss_dict[key] = total_loss_dict.get( key, torch.cuda.FloatTensor([0.0])) + loss_dict[key] args.consumed_valid_samples += mpu.get_data_parallel_world_size() \ * args.micro_batch_size \ * get_num_microbatches() collected_non_loss_data = None if process_non_loss_data_func is not None and is_last_rank(): collected_non_loss_data = forward_backward_func( forward_step_func, data_iterator, model, optimizer=None, timers=None, forward_only=True, collect_non_loss_data=True) # Move model back to the train mode. for model_module in model: model_module.train() for key in total_loss_dict: total_loss_dict[key] /= args.eval_iters * get_num_microbatches() return total_loss_dict, collected_non_loss_data def evaluate_and_print_results(prefix, forward_step_func, data_iterator, model, iteration, process_non_loss_data_func, verbose=False, args=None): """Helper function to evaluate and dump results on screen.""" writer = get_tensorboard_writer() total_loss_dict, collected_non_loss_data = evaluate( forward_step_func, data_iterator, model, process_non_loss_data_func, verbose) string = ' validation loss at {} | '.format(prefix) for key in total_loss_dict: string += '{} value: {:.6E} | '.format(key, total_loss_dict[key].item()) if "lm loss" in key: ppl = math.exp(min(20, total_loss_dict[key].item())) string += '{} PPL: {:.6E} | '.format(key, ppl) else: ppl = None if writer: writer.add_scalar('{} validation'.format(key), total_loss_dict[key].item(), iteration) writer.add_scalar('{} validation vs samples'.format(key), total_loss_dict[key].item(), args.consumed_train_samples) if args.log_validation_ppl_to_tensorboard and ppl is not None: writer.add_scalar('{} validation ppl'.format(key), ppl, iteration) writer.add_scalar('{} validation ppl vs samples'.format(key), ppl, args.consumed_train_samples) if process_non_loss_data_func is not None and writer and is_last_rank(): process_non_loss_data_func(collected_non_loss_data, iteration, writer) length = len(string) + 1 print_rank_last('-' * length) print_rank_last(string) print_rank_last('-' * length) def cyclic_iter(iter): while True: for x in iter: yield x def build_train_valid_test_data_iterators(build_train_valid_test_datasets_provider: Callable, args: argparse.Namespace, collate_fn=None): (train_dataloader, valid_dataloader, test_dataloader) = (None, None, None) print_rank_0('> building train, validation, and test datasets ...') # Backward compatibility, assume fixed batch size. if args.iteration > 0 and args.consumed_train_samples == 0: assert args.train_samples is None, \ 'only backward compatiblity support for iteration-based training' args.consumed_train_samples = args.iteration * args.global_batch_size if args.iteration > 0 and args.consumed_valid_samples == 0: if args.train_samples is None: args.consumed_valid_samples = (args.iteration // args.eval_interval) * \ args.eval_iters * args.global_batch_size # Data loader only on rank 0 of each model parallel group. if mpu.get_tensor_model_parallel_rank() == 0: # Number of train/valid/test samples. if args.train_samples: train_samples = args.train_samples else: train_samples = args.train_iters * args.global_batch_size eval_iters = (args.train_iters // args.eval_interval + 1) * \ args.eval_iters test_iters = args.eval_iters train_val_test_num_samples = [train_samples, eval_iters * args.global_batch_size, test_iters * args.global_batch_size] print_rank_0(' > datasets target sizes (minimum size):') print_rank_0(' train: {}'.format(train_val_test_num_samples[0])) print_rank_0(' validation: {}'.format(train_val_test_num_samples[1])) print_rank_0(' test: {}'.format(train_val_test_num_samples[2])) # Build the datasets. train_ds, valid_ds, test_ds = build_train_valid_test_datasets_provider( train_val_test_num_samples) # Build dataloders. train_dataloader = build_pretraining_data_loader( train_ds, args.consumed_train_samples, collate_fn=collate_fn) valid_dataloader = build_pretraining_data_loader( valid_ds, args.consumed_valid_samples, collate_fn=collate_fn) test_dataloader = build_pretraining_data_loader(test_ds, 0, collate_fn=collate_fn) # Flags to know if we need to do training/validation/testing. do_train = train_dataloader is not None and args.train_iters > 0 do_valid = valid_dataloader is not None and args.eval_iters > 0 do_test = test_dataloader is not None and args.eval_iters > 0 # Need to broadcast num_tokens and num_type_tokens. flags = torch.cuda.LongTensor( [int(do_train), int(do_valid), int(do_test)]) else: flags = torch.cuda.LongTensor([0, 0, 0]) # Broadcast num tokens. torch.distributed.broadcast(flags, mpu.get_tensor_model_parallel_src_rank(), group=mpu.get_tensor_model_parallel_group()) args.do_train = flags[0].item() args.do_valid = flags[1].item() args.do_test = flags[2].item() # Build iterators. dl_type = args.dataloader_type assert dl_type in ['single', 'cyclic'] if train_dataloader is not None: train_data_iterator = iter(train_dataloader) if dl_type == 'single' \ else iter(cyclic_iter(train_dataloader)) else: train_data_iterator = None if valid_dataloader is not None: valid_data_iterator = iter(valid_dataloader) if dl_type == 'single' \ else iter(cyclic_iter(valid_dataloader)) else: valid_data_iterator = None if test_dataloader is not None: test_data_iterator = iter(test_dataloader) if dl_type == 'single' \ else iter(cyclic_iter(test_dataloader)) else: test_data_iterator = None return train_data_iterator, valid_data_iterator, test_data_iterator