Ejemplo n.º 1
0
def prepare_model_and_optimizer(args, device):

    # Prepare model
    config = BertConfig.from_json_file(args.config_file)

    # Padding for divisibility by 8
    if config.vocab_size % 8 != 0:
        config.vocab_size += 8 - (config.vocab_size % 8)
    model = BertForPreTraining(config)

    checkpoint = None
    if not args.resume_from_checkpoint:
        global_step = 0
    else:
        if args.resume_step == -1 and not args.init_checkpoint:
            model_names = [
                f for f in os.listdir(args.output_dir) if f.endswith(".pt")
            ]
            args.resume_step = max([
                int(x.split('.pt')[0].split('_')[1].strip())
                for x in model_names
            ])

        global_step = args.resume_step if not args.init_checkpoint else 0

        if not args.init_checkpoint:
            checkpoint = torch.load(os.path.join(
                args.output_dir, "ckpt_{}.pt".format(global_step)),
                                    map_location="cpu")
        else:
            checkpoint = torch.load(args.init_checkpoint, map_location="cpu")

        model.load_state_dict(checkpoint['model'], strict=False)
        if args.phase2:
            global_step -= args.phase1_end_step
        if is_main_process():
            print("resume step from ", args.resume_step)

    model.to(device)
    param_optimizer = list(model.named_parameters())
    no_decay = ['bias', 'gamma', 'beta', 'LayerNorm']

    optimizer_grouped_parameters = [{
        'params':
        [p for n, p in param_optimizer if not any(nd in n for nd in no_decay)],
        'weight_decay':
        0.01
    }, {
        'params':
        [p for n, p in param_optimizer if any(nd in n for nd in no_decay)],
        'weight_decay':
        0.0
    }]

    optimizer = FusedLAMB(optimizer_grouped_parameters, lr=args.learning_rate)
    lr_scheduler = PolyWarmUpScheduler(optimizer,
                                       warmup=args.warmup_proportion,
                                       total_steps=args.max_steps)
    if args.fp16:

        if args.loss_scale == 0:
            model, optimizer = amp.initialize(model,
                                              optimizer,
                                              opt_level="O2",
                                              loss_scale="dynamic")
        else:
            model, optimizer = amp.initialize(model,
                                              optimizer,
                                              opt_level="O2",
                                              loss_scale=args.loss_scale)
        amp._amp_state.loss_scalers[0]._loss_scale = 2**20

    if args.resume_from_checkpoint:
        if args.phase2 or args.init_checkpoint:
            keys = list(checkpoint['optimizer']['state'].keys())
            #Override hyperparameters from previous checkpoint
            for key in keys:
                checkpoint['optimizer']['state'][key]['step'] = global_step
            for iter, item in enumerate(
                    checkpoint['optimizer']['param_groups']):
                checkpoint['optimizer']['param_groups'][iter][
                    'step'] = global_step
                checkpoint['optimizer']['param_groups'][iter][
                    't_total'] = args.max_steps
                checkpoint['optimizer']['param_groups'][iter][
                    'warmup'] = args.warmup_proportion
                checkpoint['optimizer']['param_groups'][iter][
                    'lr'] = args.learning_rate
        optimizer.load_state_dict(checkpoint['optimizer'])  # , strict=False)

        # Restore AMP master parameters
        if args.fp16:
            optimizer._lazy_init_maybe_master_weights()
            optimizer._amp_stash.lazy_init_called = True
            optimizer.load_state_dict(checkpoint['optimizer'])
            for param, saved_param in zip(amp.master_params(optimizer),
                                          checkpoint['master params']):
                param.data.copy_(saved_param.data)

    if args.local_rank != -1:
        if not args.allreduce_post_accumulation:
            model = DDP(
                model,
                message_size=250000000,
                gradient_predivide_factor=torch.distributed.get_world_size())
        else:
            flat_dist_call([param.data for param in model.parameters()],
                           torch.distributed.broadcast, (0, ))
    elif args.n_gpu > 1:
        model = torch.nn.DataParallel(model)

    return model, optimizer, lr_scheduler, checkpoint, global_step
def prepare_model_and_optimizer(args, device):
    global_step = 0
    args.resume_step = 0
    checkpoint = None

    config = BertConfig.from_json_file(args.bert_config_path)
    config.fused_mha = args.fused_mha
    config.fused_gelu_bias = args.fused_gelu_bias
    config.dense_seq_output = args.dense_seq_output
    config.unpad = args.unpad
    config.pad = args.pad
    config.fuse_qkv = not args.disable_fuse_qkv
    config.fuse_scale = not args.disable_fuse_scale
    config.fuse_mask = not args.disable_fuse_mask
    config.fuse_dropout = args.enable_fuse_dropout
    config.apex_softmax = not args.disable_apex_softmax
    config.enable_stream = args.enable_stream
    if config.fuse_mask == True: config.apex_softmax = True
    if config.pad == False: config.enable_stream = True
    if config.unpad == True: config.fused_mha = False

    # Padding for divisibility by 8
    if config.vocab_size % 8 != 0:
        config.vocab_size += 8 - (config.vocab_size % 8)

    # Load from Pyt checkpoint - either given as init_checkpoint, or picked up from output_dir if found
    if args.init_checkpoint is not None or found_resume_checkpoint(args):
        # Prepare model

        model = BertForPreTraining(config)
        if args.init_checkpoint is None: # finding checkpoint in output_dir
            checkpoint_str = "phase2_ckpt_*.pt" if args.phase2 else "phase1_ckpt_*.pt"
            model_names = [f for f in glob.glob(os.path.join(args.output_dir, checkpoint_str))]
            global_step = max([int(x.split('.pt')[0].split('_')[-1].strip()) for x in model_names])
            args.resume_step = global_step #used for throughput computation

            resume_init_checkpoint = os.path.join(args.output_dir, checkpoint_str.replace("*", str(global_step)))
            print("Setting init checkpoint to %s - which is the latest in %s" %(resume_init_checkpoint, args.output_dir))
            checkpoint=torch.load(resume_init_checkpoint, map_location="cpu")
        else:
            checkpoint=torch.load(args.init_checkpoint, map_location="cpu")["model"]

        # Fused MHA requires a remapping of checkpoint parameters
        if config.fused_mha:
            checkpoint_remapped = remap_attn_parameters(checkpoint)
            model.load_state_dict(checkpoint_remapped, strict=False)
        else:
            model.load_state_dict(checkpoint, strict=True)
    else: #Load from TF Checkpoint
        model = BertForPreTraining.from_pretrained(args.init_tf_checkpoint, from_tf=True, config=config)


    model.to(device)
    param_optimizer = list(model.named_parameters())
    no_decay = ['bias', 'gamma', 'beta', 'LayerNorm']

    optimizer_grouped_parameters = [
        {'params': [p for n, p in param_optimizer if not any(nd in n for nd in no_decay)], 'weight_decay': args.weight_decay_rate},
        {'params': [p for n, p in param_optimizer if any(nd in n for nd in no_decay)], 'weight_decay': 0.0}]

    mlperf_logger.log_event(key=mlperf_logger.constants.OPT_BASE_LR,
                            value=args.learning_rate, sync=False)
    optimizer = FusedLAMB(optimizer_grouped_parameters,
                          lr=args.learning_rate,
                          betas=(args.opt_lamb_beta_1, args.opt_lamb_beta_2))
    mlperf_logger.log_event(key='opt_epsilon', value=optimizer.defaults['eps'],
                            sync=False)
    b1, b2 = optimizer.defaults['betas']
    mlperf_logger.log_event(key='opt_lamb_beta_1', value=b1, sync=False)
    mlperf_logger.log_event(key='opt_lamb_beta_2', value=b2, sync=False)
    mlperf_logger.log_event(key='opt_lamb_weight_decay_rate',
                            value=optimizer.defaults['weight_decay'],
                            sync=False)

    if args.warmup_steps == 0:
        warmup_steps = int(args.max_steps * args.warmup_proportion)
        warmup_start = 0
    else:
        warmup_steps = args.warmup_steps
        warmup_start = args.start_warmup_step
    lr_scheduler = LinearWarmupPolyDecayScheduler(optimizer, start_warmup_steps=warmup_start, warmup_steps=warmup_steps,
                                                  total_steps=args.max_steps, end_learning_rate=0.0, degree=1.0)
    
                           
    if args.fp16:

        if args.loss_scale == 0:
            model, optimizer = amp.initialize(model, optimizer, opt_level="O2", loss_scale="dynamic")
        else:
            model, optimizer = amp.initialize(model, optimizer, opt_level="O2", loss_scale=args.loss_scale)
        amp._amp_state.loss_scalers[0]._loss_scale = float(os.getenv("INIT_LOSS_SCALE", 2**20))


    if found_resume_checkpoint(args):
        optimizer.load_state_dict(checkpoint['optimizer']) #restores m,v states (only if resuming checkpoint, not for init_checkpoint and init_tf_checkpoint for now)

        # Restore AMP master parameters          
        if args.fp16:
            optimizer._lazy_init_maybe_master_weights()
            optimizer._amp_stash.lazy_init_called = True
            optimizer.load_state_dict(checkpoint['optimizer'])
            for param, saved_param in zip(amp.master_params(optimizer), checkpoint['master params']):
                param.data.copy_(saved_param.data)

    if args.local_rank != -1:
        if not args.allreduce_post_accumulation:
            model = DDP(model, message_size=250000000, gradient_predivide_factor=torch.distributed.get_world_size())
        else:
            flat_dist_call([param.data for param in model.parameters()], torch.distributed.broadcast, (0,) )

    return model, optimizer, lr_scheduler, checkpoint, global_step