arguments.py

# Copyright (c) 2024, NVIDIA CORPORATION. All rights reserved.

"""Megatron arguments."""

import argparse
import dataclasses
import json
import os
import torch
import types

import torch.nn.functional as F
from megatron.core.models.retro.utils import (
    get_config_path as get_retro_config_path,
    get_gpt_data_dir as get_retro_data_dir,
)
from megatron.core.transformer import TransformerConfig


def parse_args(extra_args_provider=None, ignore_unknown_args=False):
    """Parse all arguments."""
    parser = argparse.ArgumentParser(description='Megatron-LM Arguments',
                                     allow_abbrev=False)

    # Standard arguments.
    parser = _add_network_size_args(parser)
    parser = _add_regularization_args(parser)
    parser = _add_training_args(parser)
    parser = _add_initialization_args(parser)
    parser = _add_learning_rate_args(parser)
    parser = _add_checkpointing_args(parser)
    parser = _add_mixed_precision_args(parser)
    parser = _add_distributed_args(parser)
    parser = _add_validation_args(parser)
    parser = _add_data_args(parser)
    parser = _add_autoresume_args(parser)
    parser = _add_biencoder_args(parser)
    parser = _add_vision_args(parser)
    parser = _add_moe_args(parser)
    parser = _add_logging_args(parser)
    parser = _add_straggler_detector_args(parser)
    parser = _add_inference_args(parser)
    parser = _add_transformer_engine_args(parser)
    parser = _add_retro_args(parser)
    parser = _add_experimental_args(parser)

    # Custom arguments.
    if extra_args_provider is not None:
        parser = extra_args_provider(parser)

    # Parse.
    if ignore_unknown_args:
        args, _ = parser.parse_known_args()
    else:
        args = parser.parse_args()

    # Experimental yaml
    if args.yaml_cfg is not None:
        from .yaml_arguments import load_yaml
        assert args.yaml_cfg and args.use_mcore_models, "To use yaml, mcore must be enabled"
        args = load_yaml(args.yaml_cfg)

    # Distributed args.
    if args.use_mpi:
        global_rank = int(os.getenv('OMPI_COMM_WORLD_RANK', 0))
        local_rank = int(os.getenv('OMPI_COMM_WORLD_LOCAL_RANK', 0))
        world_size = int(os.getenv('OMPI_COMM_WORLD_SIZE', 1))

        os.environ['RANK'] = str(global_rank)
        os.environ['LOCAL_RANK'] = str(local_rank)
        os.environ['WORLD_SIZE'] = str(world_size)

    args.rank = int(os.getenv('RANK', '0'))
    args.world_size = int(os.getenv("WORLD_SIZE", '1'))

    return args


def load_retro_config(retro_project_dir):
    '''Load Retro's config.json.'''

    # Retro config path.
    retro_config_path = get_retro_config_path(retro_project_dir)
    assert os.path.exists(retro_config_path), \
        "Retro project dir missing config.json."

    # Load retro config.
    with open(retro_config_path) as f:
        retro_config = types.SimpleNamespace(**json.load(f))

    return retro_config


def load_retro_args(args):
    """Load predefined args from Retro config (if applicable).

    When using Retro (or GPT for comparison purposes), data arguments are
    overridden by the saved config.json within the Retro project directory. This
    is to ensure that the data used for pretraining is consistent with the data
    that was preprocessed using the Retro preprocessing pipeline (see
    `tools/retro/preprocess_data.py`).
    """

    # Return if no project directory is specified.
    if args.retro_project_dir is None:
        return

    # Load retro config.
    retro_config = load_retro_config(args.retro_project_dir)

    # Retro data path is relative to project dir (via hard or soft links).
    data_dir = get_retro_data_dir(args.retro_project_dir)
    data_path = list(retro_config.retro_gpt_data_path)
    if len(data_path) % 2 == 0:
        for i in range(len(data_path) - 1, -1, -2):
            data_path[i] = os.path.join(data_dir, data_path[i])
    else:
        assert len(data_path) == 1
        data_path[0] = os.path.join(data_dir, data_path[0])

    # Update args.
    args.data_cache_path = retro_config.retro_gpt_data_cache_path
    args.data_path = data_path if args.data_path is None else args.data_path
    args.eval_interval = retro_config.retro_gpt_eval_interval
    args.eval_iters = retro_config.retro_gpt_eval_iters
    args.global_batch_size = retro_config.retro_gpt_global_batch_size
    args.max_position_embeddings = retro_config.retro_gpt_seq_length
    args.merge_file = os.path.join(
        args.retro_project_dir,
        retro_config.retro_gpt_merge_file,
    ) if retro_config.retro_gpt_merge_file is not None else None
    args.seed = retro_config.retro_gpt_seed
    args.seq_length = retro_config.retro_gpt_seq_length
    args.tokenizer_model = os.path.join(
        args.retro_project_dir,
        retro_config.retro_gpt_tokenizer_model,
    ) if retro_config.retro_gpt_tokenizer_model is not None else None
    args.tokenizer_type = retro_config.retro_gpt_tokenizer_type
    args.train_samples = retro_config.retro_gpt_train_samples
    args.vocab_file = os.path.join(
        args.retro_project_dir,
        retro_config.retro_gpt_vocab_file,
    ) if retro_config.retro_gpt_vocab_file is not None else None

    # Retro-specific args.
    args.retro_block_size = retro_config.retro_block_size
    args.retro_chunk_length = retro_config.retro_gpt_chunk_length
    args.retro_neighbor_dirs = retro_config.retro_neighbor_dirs
    args.retro_split_preprocessing = retro_config.retro_gpt_split
    args.retro_bert_tokenizer_type = retro_config.retro_bert_tokenizer_type
    args.retro_bert_vocab_file = retro_config.retro_bert_vocab_file


def validate_args(args, defaults={}):

    # Load saved args from Retro (if applicable).
    load_retro_args(args)

    # Tensor model parallel size.
    args.tensor_model_parallel_size = min(
        args.tensor_model_parallel_size, args.world_size)
    assert args.world_size % args.tensor_model_parallel_size == 0, 'world size'\
        ' ({}) is not divisible by tensor model parallel size ({})'.format(
            args.world_size, args.tensor_model_parallel_size)

    # Pipeline model parallel size.
    args.pipeline_model_parallel_size = min(
        args.pipeline_model_parallel_size,
        (args.world_size // args.tensor_model_parallel_size))
    args.transformer_pipeline_model_parallel_size = (
        args.pipeline_model_parallel_size - 1
        if args.standalone_embedding_stage else
        args.pipeline_model_parallel_size
    )

    # Checks.
    model_parallel_size = args.pipeline_model_parallel_size * \
                          args.tensor_model_parallel_size
    assert args.world_size % (model_parallel_size * args.context_parallel_size) == 0, \
        'world size ({}) is not divisible by tensor parallel size ({}) times ' \
        'pipeline parallel size ({}) times context parallel size ({})'.format(
        args.world_size, args.tensor_model_parallel_size,
        args.pipeline_model_parallel_size, args.context_parallel_size)
    args.data_parallel_size = args.world_size // (model_parallel_size * args.context_parallel_size)
    if args.rank == 0:
        print('using world size: {}, data-parallel size: {}, '
              'context-parallel size: {} '
              'tensor-model-parallel size: {}, '
              'pipeline-model-parallel size: {} '.format(
                  args.world_size, args.data_parallel_size,
                  args.context_parallel_size,
                  args.tensor_model_parallel_size,
                  args.pipeline_model_parallel_size), flush=True)
    if args.pipeline_model_parallel_size > 1:
        if args.pipeline_model_parallel_split_rank is not None:
            assert args.pipeline_model_parallel_split_rank < \
                    args.pipeline_model_parallel_size, 'split rank needs'\
                    ' to be less than pipeline model parallel size ({})'.format(
                            args.pipeline_model_parallel_size)

    if args.tp_comm_overlap:
        assert args.sequence_parallel is True, 'Tensor parallel communication/GEMM overlap can happen only when sequence parallelism is enabled'

    # Deprecated arguments
    assert args.batch_size is None, '--batch-size argument is no longer ' \
        'valid, use --micro-batch-size instead'
    del args.batch_size
    assert args.warmup is None, '--warmup argument is no longer valid, use ' \
        '--lr-warmup-fraction instead'
    del args.warmup
    assert args.model_parallel_size is None, '--model-parallel-size is no ' \
        'longer valid, use --tensor-model-parallel-size instead'
    del args.model_parallel_size

    if args.checkpoint_activations:
        if args.rank == 0:
            print('--checkpoint-activations is no longer valid, use --recompute-activations, '
                  'or, for more control, --recompute-granularity and --recompute-method.')
        exit()
    del args.checkpoint_activations

    if args.recompute_activations:
        args.recompute_granularity = 'selective'
    del args.recompute_activations

    # Set input defaults.
    for key in defaults:
        # For default to be valid, it should not be provided in the
        # arguments that are passed to the program. We check this by
        # ensuring the arg is set to None.
        if getattr(args, key, None) is not None:
            if args.rank == 0:
                print('WARNING: overriding default arguments for {key}:{v} \
                       with {key}:{v2}'.format(key=key, v=defaults[key],
                                               v2=getattr(args, key)),
                                               flush=True)
        else:
            setattr(args, key, defaults[key])

    # Batch size.
    assert args.micro_batch_size is not None
    assert args.micro_batch_size > 0
    if args.global_batch_size is None:
        args.global_batch_size = args.micro_batch_size * args.data_parallel_size
        if args.rank == 0:
            print('setting global batch size to {}'.format(
                args.global_batch_size), flush=True)
    assert args.global_batch_size > 0
    if args.num_layers_per_virtual_pipeline_stage is not None:
        assert args.pipeline_model_parallel_size > 2, \
            'pipeline-model-parallel size should be greater than 2 with ' \
            'interleaved schedule'
        assert args.num_layers % args.transformer_pipeline_model_parallel_size == 0, \
            'number of layers should be divisible by the pipeline parallel size'
        num_layers_per_pipeline_stage = args.num_layers // args.transformer_pipeline_model_parallel_size
        assert num_layers_per_pipeline_stage % args.num_layers_per_virtual_pipeline_stage == 0, \
            'number of layers per pipeline stage must be divisible number of layers per virtual pipeline stage'
        args.virtual_pipeline_model_parallel_size = num_layers_per_pipeline_stage // \
            args.num_layers_per_virtual_pipeline_stage
    else:
        args.virtual_pipeline_model_parallel_size = None
        # Overlap P2P communication is disabled if not using the interleaved schedule.
        args.overlap_p2p_comm = False
        if args.rank == 0:
            print('WARNING: Setting args.overlap_p2p_comm to False since non-interleaved '
                  'schedule does not support overlapping p2p communication')

    if args.overlap_param_gather:
        assert args.use_distributed_optimizer, \
            '--overlap-param-gather only supported with distributed optimizer'
        assert args.overlap_grad_reduce, \
            '--overlap-grad-reduce should be turned on when using --overlap-param-gather'
        assert args.use_mcore_models, \
            '--overlap-param-gather only supported with MCore models'

    # Parameters dtype.
    args.params_dtype = torch.float
    if args.fp16:
        assert not args.bf16
        args.params_dtype = torch.half
        # Turn off checking for NaNs in loss and grads if using dynamic loss scaling,
        # where NaNs in grads / loss are signal to the loss scaler.
        if not args.loss_scale:
            args.check_for_nan_in_loss_and_grad = False
            if args.rank == 0:
                print('WARNING: Setting args.check_for_nan_in_loss_and_grad to False since '
                      'dynamic loss scaling is being used')
    if args.bf16:
        assert not args.fp16
        args.params_dtype = torch.bfloat16
        # bfloat16 requires gradient accumulation and all-reduce to
        # be done in fp32.
        if not args.accumulate_allreduce_grads_in_fp32:
            args.accumulate_allreduce_grads_in_fp32 = True
            if args.rank == 0:
                print('accumulate and all-reduce gradients in fp32 for '
                      'bfloat16 data type.', flush=True)

    if args.rank == 0:
        print('using {} for parameters ...'.format(args.params_dtype),
              flush=True)

    if args.dataloader_type is None:
        args.dataloader_type = 'single'

    # Consumed tokens.
    args.consumed_train_samples = 0
    args.consumed_valid_samples = 0
    args.consumed_train_tokens = 0

    # Support for variable sequence lengths across batches/microbatches.
    # set it if the dataloader supports generation of variable sequence lengths
    # across batches/microbatches. Due to additional communication overhead
    # during pipeline parallelism, it should not be set if sequence length
    # is constant during training.
    args.variable_seq_lengths = False

    # Iteration-based training.
    if args.train_iters:
        # If we use iteration-based training, make sure the
        # sample-based options are off.
        assert args.train_samples is None, \
            'expected iteration-based training'
        assert args.lr_decay_samples is None, \
            'expected iteration-based learning rate decay'
        assert args.lr_warmup_samples == 0, \
            'expected iteration-based learning rate warmup'
        assert args.rampup_batch_size is None, \
            'expected no batch-size rampup for iteration-based training'
        if args.lr_warmup_fraction is not None:
            assert args.lr_warmup_iters == 0, \
                'can only specify one of lr-warmup-fraction and lr-warmup-iters'

    # Sample-based training.
    if args.train_samples:
        # If we use sample-based training, make sure the
        # iteration-based options are off.
        assert args.train_iters is None, \
            'expected sample-based training'
        assert args.lr_decay_iters is None, \
            'expected sample-based learning rate decay'
        assert args.lr_warmup_iters == 0, \
            'expected sample-based learnig rate warmup'
        if args.lr_warmup_fraction is not None:
            assert args.lr_warmup_samples == 0, \
                'can only specify one of lr-warmup-fraction ' \
                'and lr-warmup-samples'

    if args.num_layers is not None:
        assert args.encoder_num_layers is None, \
            'cannot have both num-layers and encoder-num-layers specified'
        args.encoder_num_layers = args.num_layers
    else:
        assert args.encoder_num_layers is not None, \
            'either num-layers or encoder-num-layers should be specified'
        args.num_layers = args.encoder_num_layers

    # Check required arguments.
    required_args = ['num_layers', 'hidden_size', 'num_attention_heads',
                     'max_position_embeddings']
    for req_arg in required_args:
        _check_arg_is_not_none(args, req_arg)

    # Checks.
    if args.ffn_hidden_size is None:
        if args.swiglu:
            # reduce the dimnesion for MLP since projections happens on
            # two linear layers. this keeps the number of paramters in
            # the same ballpark as the counterpart with 4*h size
            # we keep it a multiple of 64, which means the actual tensor size
            # will be a multiple of 64 / tp_size
            args.ffn_hidden_size = int((4 * args.hidden_size * 2 / 3) / 64) * 64
        else:
            args.ffn_hidden_size = 4 * args.hidden_size

    if args.kv_channels is None:
        assert args.hidden_size % args.num_attention_heads == 0
        args.kv_channels = args.hidden_size // args.num_attention_heads

    if args.seq_length is not None:
        assert args.encoder_seq_length is None
        args.encoder_seq_length = args.seq_length
    else:
        assert args.encoder_seq_length is not None
        args.seq_length = args.encoder_seq_length

    if args.seq_length is not None:
        assert args.max_position_embeddings >= args.seq_length
    if args.decoder_seq_length is not None:
        assert args.max_position_embeddings >= args.decoder_seq_length
    if args.lr is not None:
        assert args.min_lr <= args.lr
    if args.save is not None:
        assert args.save_interval is not None
    # Mixed precision checks.
    if args.fp16_lm_cross_entropy:
        assert args.fp16, 'lm cross entropy in fp16 only support in fp16 mode.'
    if args.fp32_residual_connection:
        assert args.fp16 or args.bf16, \
            'residual connection in fp32 only supported when using fp16 or bf16.'

    if args.moe_grouped_gemm:
        assert args.bf16, 'Currently GroupedGEMM for MoE only supports bf16 dtype.'
        dc = torch.cuda.get_device_capability()
        assert dc[0] >= 8, "Unsupported compute capability for GroupedGEMM kernels."

    if args.weight_decay_incr_style == 'constant':
        assert args.start_weight_decay is None
        assert args.end_weight_decay is None
        args.start_weight_decay = args.weight_decay
        args.end_weight_decay = args.weight_decay
    else:
        assert args.start_weight_decay is not None
        assert args.end_weight_decay is not None

    TORCH_MAJOR = int(torch.__version__.split('.')[0])
    TORCH_MINOR = int(torch.__version__.split('.')[1])
    # Persistent fused layer norm.
    if TORCH_MAJOR < 1 or (TORCH_MAJOR == 1 and TORCH_MINOR < 11):
        args.no_persist_layer_norm = True
        if args.rank == 0:
            print('Persistent fused layer norm kernel is supported from '
                  'pytorch v1.11 (nvidia pytorch container paired with v1.11). '
                  'Defaulting to no_persist_layer_norm=True')

    # Activation recomputing.
    if args.distribute_saved_activations:
        assert args.tensor_model_parallel_size > 1, 'can distribute ' \
            'recomputed activations only across tensor model ' \
            'parallel groups'
        assert args.recompute_granularity == 'full', \
            'distributed recompute activations is only '\
            'application to full recompute granularity'
        assert args.recompute_method is not None, \
            'for distributed recompute activations to work you '\
            'need to use a recompute method '
        assert (TORCH_MAJOR, TORCH_MINOR) >= (1, 10), \
            'distributed recompute activations are supported for pytorch ' \
            'v1.10 and above (Nvidia Pytorch container >= 21.07). Current ' \
            'pytorch version is v%s.%s.' % (TORCH_MAJOR, TORCH_MINOR)

    if args.recompute_granularity == 'selective':
        assert args.recompute_method is None, \
            'recompute method is not yet supported for ' \
            'selective recomputing granularity'

    # disable sequence parallelism when tp=1
    # to avoid change in numerics when
    # sequence_parallelism is enabled.
    if args.tensor_model_parallel_size == 1:
        args.sequence_parallel = False

    # disable async_tensor_model_parallel_allreduce when
    # model parallel memory optimization is enabled
    if args.sequence_parallel:
        args.async_tensor_model_parallel_allreduce = False

    if os.environ.get('CUDA_DEVICE_MAX_CONNECTIONS') != "1":
        if args.sequence_parallel:
            raise RuntimeError(
                "Using sequence parallelism requires setting the environment variable "
                "CUDA_DEVICE_MAX_CONNECTIONS to 1")
        if args.async_tensor_model_parallel_allreduce:
            raise RuntimeError(
                "Using async gradient all reduce requires setting the environment "
                "variable CUDA_DEVICE_MAX_CONNECTIONS to 1")

    # Disable bias gelu fusion if we are disabling bias altogether
    if not args.add_bias_linear:
        args.bias_gelu_fusion = False

    # Retro checks.
    if args.retro_add_retriever:

        # Train samples should be auto-loaded.
        assert args.train_samples is not None, \
            "args.train_samples should be auto-loaded from the retro config."

        # Sequence parallelism unsupported.
        assert not args.sequence_parallel, \
            "retro currently does not support sequence parallelism."

        # Pipeline parallelism unsupported.
        assert args.pipeline_model_parallel_size == 1, \
            "retro currently does not support pipeline parallelism."

    if args.decoupled_lr is not None or args.decoupled_min_lr is not None:
        assert args.use_mcore_models, \
            '--decoupled-lr and --decoupled-min-lr only supported by Megatron Core, please add --use-mcore-models.'

    # Skip train iterations
    if args.skip_train_iteration_range is not None:
        import collections

        args.skip_train_iteration_range = [
            list(map(int, range_.split("-"))) for range_ in args.skip_train_iteration_range
        ]
        args.skip_train_iteration_range.sort()
        skip_train_iteration_range = collections.deque()
        for range_ in args.skip_train_iteration_range:
            if len(range_) == 2:
                start, end = range_
                assert end >= start, "end of skip range cannot be smaller than start of skip range"
                # merge overlapping intervals (e.g. 1-5 2-6 -> 1-6)
                if not skip_train_iteration_range:
                    skip_train_iteration_range.append([start, end])
                elif skip_train_iteration_range[-1][1] >= start:
                    skip_train_iteration_range[-1][1] = max(end, skip_train_iteration_range[-1][1])
                else:
                    skip_train_iteration_range.append([start, end])
            else:
                raise ValueError(
                    "skip train iterations should be specified as two numbers, i.e. start-end"
                )
        args.skip_train_iteration_range = skip_train_iteration_range

    # Legacy RoPE arguments
    if args.use_rotary_position_embeddings:
        args.position_embedding_type = 'rope'
    if args.rotary_interleaved and args.apply_rope_fusion:
        raise RuntimeError('--rotary-interleaved does not work with rope_fusion.')
    if args.rotary_interleaved and not args.use_mcore_models:
        raise RuntimeError('--rotary-interleaved only support Megatron Core, please add --use-mcore-models.')

    # Would just need to add 'NoPE' as a position_embedding_type to support this, but for now
    # don't allow it to keep things simple
    if not args.add_position_embedding and args.position_embedding_type != 'rope':
        raise RuntimeError('--no-position-embedding is deprecated, use --position-embedding-type')

    # MoE Spec check
    if args.num_experts is not None:
        assert args.spec is None, "Model Spec must be None when using MoEs"
        if args.tensor_model_parallel_size > 1:
            assert args.sequence_parallel, \
                "When using MoE and tensor parallelism, sequence parallelism must be used."

    # Expert parallelism check
    if args.expert_model_parallel_size > 1:
        assert args.num_experts is not None, "num_experts must be non None to use expert model parallelism"
        assert args.num_experts % args.expert_model_parallel_size == 0, \
            "Number of experts should be a multiple of expert model parallel_size."
        assert not args.fp16, \
            "Expert parallelism is not supported with fp16 training."

    # Distributed checkpointing checks
    if args.use_dist_ckpt and not args.use_mcore_models:
        raise RuntimeError('--use-dist-ckpt only support Megatron Core, please add --use-mcore-models.')

    if args.use_tp_pp_dp_mapping:
        assert args.context_parallel_size * args.expert_model_parallel_size <= 1, \
            "context_parallel and expert_model_parallel can't be used with tp-pp-dp mapping."

    # Print arguments.
    _print_args("arguments", args)

    return args


def _print_args(title, args):
    """Print arguments."""
    if args.rank == 0:
        print(f'------------------------ {title} ------------------------',
              flush=True)
        str_list = []
        for arg in vars(args):
            dots = '.' * (48 - len(arg))
            str_list.append('  {} {} {}'.format(arg, dots, getattr(args, arg)))
        for arg in sorted(str_list, key=lambda x: x.lower()):
            print(arg, flush=True)
        print(f'-------------------- end of {title} ---------------------',
              flush=True)


def _check_arg_is_not_none(args, arg):
    assert getattr(args, arg) is not None, '{} argument is None'.format(arg)


def core_transformer_config_from_args(args, config_class=None):

    # Config class.
    config_class = config_class or TransformerConfig

    # Translate args to core transformer configuration
    kw_args = {}
    for f in dataclasses.fields(config_class):
        if hasattr(args, f.name):
            kw_args[f.name] = getattr(args, f.name)
    kw_args['persist_layer_norm'] = not args.no_persist_layer_norm
    kw_args['layernorm_zero_centered_gamma'] = args.apply_layernorm_1p
    kw_args['layernorm_epsilon'] = args.norm_epsilon
    kw_args['deallocate_pipeline_outputs'] = True
    kw_args['pipeline_dtype'] = args.params_dtype
    kw_args['batch_p2p_comm'] = not args.overlap_p2p_comm
    kw_args['num_moe_experts'] = args.num_experts
    kw_args['rotary_interleaved'] = args.rotary_interleaved
    if args.swiglu:
        kw_args['activation_func'] = F.silu
        kw_args['gated_linear_unit'] = True
        kw_args['bias_activation_fusion'] = args.bias_swiglu_fusion
    else:
        kw_args['bias_activation_fusion'] = args.bias_gelu_fusion
    if args.squared_relu:
        assert not args.swiglu
        def squared_relu(x):
            return torch.pow(F.relu(x), 2)
        kw_args['activation_func'] = squared_relu
    if args.init_method_xavier_uniform:
        kw_args['init_method'] = torch.nn.init.xavier_uniform_
        kw_args['scaled_init_method'] = torch.nn.init.xavier_uniform_
    if args.group_query_attention:
        kw_args['num_query_groups'] = args.num_query_groups
    else:
        kw_args['num_query_groups'] = None

    # Return config.
    return config_class(**kw_args)


def _add_transformer_engine_args(parser):
    group = parser.add_argument_group(title='Transformer-Engine')

    group.add_argument('--fp8-format', default=None,
                       choices=['e4m3', 'hybrid'],
                       help='Which fp8 format scheme to use for FP8 tensors in the forward and backward pass',
                       dest='fp8')
    group.add_argument('--fp8-margin', type=int, default=0,
                       help='Scaling margin for fp8',
                       dest='fp8_margin')
    group.add_argument('--fp8-interval', type=int, default=1,
                       help='Scaling update interval for fp8',
                       dest='fp8_interval')
    group.add_argument('--fp8-amax-history-len', type=int, default=1,
                       help='Number of steps for which amax history is recorded per tensor',
                       dest='fp8_amax_history_len')
    group.add_argument('--fp8-amax-compute-algo', default='most_recent',
                       choices=['most_recent', 'max'],
                       help='Algorithm for computing amax from history',
                       dest='fp8_amax_compute_algo')
    group.add_argument('--no-fp8-wgrad', action='store_false',
                       help='Execute wgrad in higher precision even for FP8 runs',
                       dest='fp8_wgrad')
    group.add_argument('--transformer-impl', default='transformer_engine',
                       choices=['local', 'transformer_engine'],
                       help='Which Transformer implementation to use.')

    return parser


def _add_inference_args(parser):
    group = parser.add_argument_group(title='inference')

    group.add_argument('--inference-batch-times-seqlen-threshold',
                       type=int, default=512,
                       help='During inference, if batch-size times '
                       'sequence-length is smaller than this threshold '
                       'then we will not use pipelining, otherwise we will.')
    group.add_argument('--max-tokens-to-oom',
                       type=int, default=12000,
                       help='Maximum number of tokens during inference'
                       'tokens here is # in prompt + # to generate'
                       'Allows us to throw an error before OOM crashes server')
    group.add_argument('--output-bert-embeddings', action='store_true',
                       help='Output Bert embeddings (via mean pooling) from '
                       'model, rather than its binary head output or entire '
                       'hidden batch.')
    group.add_argument('--bert-embedder-type', default="megatron",
                       choices=["megatron", "huggingface"],
                       help='Select either Megatron or Huggingface as the '
                       'Bert embedder.')

    return parser


def _add_retro_args(parser):
    group = parser.add_argument_group(title='retro')

    group.add_argument('--retro-project-dir', default=None,
                       help='Retro project directory, which contains the '
                       'preprocessed data for pretraining. This directory '
                       'is built during preprocessing (see '
                       'tools/retro/README.md), and contains subdirectories '
                       'for the chunk database and pretraining neighbors.')
    group.add_argument('--retro-add-retriever',
                       action='store_true', default=False,
                       help='Add a retriever to the transformer, for use in '
                       'pretraining a Retro model.')
    group.add_argument('--retro-cyclic-train-iters', type=int, default=None,
                       help='Set number of training iterations for cyclic '
                       'Retro training.')
    group.add_argument('--retro-encoder-layers', type=int, default=2,
                       help='Number of layers to use for the retrieval '
                       'encoder.')
    group.add_argument('--retro-encoder-hidden-dropout',
                       type=float, default=0.1, help='Hidden dropout for '
                       'retrieval encoder.')
    group.add_argument('--retro-encoder-attention-dropout',
                       type=float, default=0.1, help='Attention dropout for '
                       'retrieval encoder.')
    group.add_argument("--retro-num-neighbors", type=int, default=2,
                       help='Number of neighbors to retrieve during '
                       'pretraining.')
    group.add_argument("--retro-num-retrieved-chunks", type=int, default=2,
                       help='Number of chunks to retrieve from the retrieval '
                       'database.')
    group.add_argument("--retro-attention-gate", type=float, default=1,
                       help="Gated cross attention.")
    group.add_argument("--retro-no-verify-neighbor-count", action="store_false",
                       dest="retro_verify_neighbor_count",
                       help="Skip verifying that len(GPT dataset) == len(saved "
                       "neighbors).")

    # Enforce argument naming convention.
    for action in group._group_actions:
        prefix = action.dest.split("_")[0]
        assert prefix == "retro", \
            "Retro args must be prefixed with '--retro-*', for consistent " \
            "styling. Please fix '%s'." % ", ".join(action.option_strings)

    return parser


def _add_network_size_args(parser):
    group = parser.add_argument_group(title='network size')

    group.add_argument('--num-layers', type=int, default=None,
                       help='Number of transformer layers.')
    group.add_argument('--encoder-num-layers', type=int, default=None,
                       help='Number of encoder transformer layers.')
    group.add_argument('--decoder-num-layers', type=int, default=None,
                       help='Number of decoder transformer layers.')
    group.add_argument('--hidden-size', type=int, default=None,
                       help='Tansformer hidden size.')
    group.add_argument('--ffn-hidden-size', type=int, default=None,
                       help='Transformer Feed-Forward Network hidden size. '
                       'This is set to 4*hidden-size if not provided')
    group.add_argument('--num-attention-heads', type=int, default=None,
                       help='Number of transformer attention heads.')
    group.add_argument('--kv-channels', type=int, default=None,
                       help='Projection weights dimension in multi-head '
                       'attention. This is set to '
                       '   args.hidden_size // args.num_attention_heads '
                       'if not provided.')
    group.add_argument('--group-query-attention', action='store_true',
                          help='Use group-query attention.')
    group.add_argument('--num-query-groups', type=int, default=1)

    group.add_argument('--max-position-embeddings', type=int, default=None,
                       help='Maximum number of position embeddings to use. '
                       'This is the size of position embedding.')
    group.add_argument('--position-embedding-type', type=str, default='learned_absolute',
                       choices=['learned_absolute', 'rope'],
                       help='Position embedding type.')
    group.add_argument('--use-rotary-position-embeddings', action='store_true',
                       help='Use rotary positional embeddings or not. '
                       'Deprecated: use --position-embedding-type')
    group.add_argument('--rotary-percent', type=float, default=1.0,
                       help='Percent of rotary dimension to use, default 100%%')
    group.add_argument('--rotary-interleaved', action='store_true',
                          help='Use interleaved rotary embedding.')
    group.add_argument('--rope-theta', type=float, default=10000)
    group.add_argument("--use-embedding-scaling", action="store_true")
    group.add_argument('--rotary-seq-len-interpolation-factor', type=int, default=None,
                       help='Sequence length interpolation factor for rotary embeddings.')
    group.add_argument('--no-position-embedding',
                       action='store_false',
                       help='Disable position embedding. Deprecated: use --position-embedding-type',
                       dest='add_position_embedding')
    group.add_argument('--make-vocab-size-divisible-by', type=int, default=128,
                       help='Pad the vocab size to be divisible by this value.'
                       'This is added for computational efficieny reasons.')
    group.add_argument('--normalization', default='LayerNorm',
                       choices=['LayerNorm', 'RMSNorm'],
                       help='Which normalization technique to use.')
    group.add_argument('--norm-epsilon', type=float, default=1e-5,
                       help='Epsilon for layer norm and RMS norm.')
    group.add_argument('--apply-layernorm-1p', action='store_true',
                       help='Adjust LayerNorm weights such that they are centered '
                       'around zero. This improves numerical stability.')
    group.add_argument('--apply-residual-connection-post-layernorm',
                       action='store_true',
                       help='If set, use original BERT residula connection '
                       'ordering.')
    group.add_argument('--openai-gelu', action='store_true',
                       help='Use OpenAIs GeLU implementation. This option'
                       'should not be used unless for backward compatibility'
                       'reasons.')
    group.add_argument('--squared-relu', action='store_true',
                       help='Use squared relu activation instead of default gelu')
    group.add_argument('--swiglu', action='store_true',
                       help='Use gated linear units and SiLU activation instead of default gelu')
    group.add_argument('--onnx-safe', type=bool, required=False,
                       help='Use workarounds for known problems with '
                       'Torch ONNX exporter')
    group.add_argument('--bert-no-binary-head', action='store_false',
                       help='Disable BERT binary head.',
                       dest='bert_binary_head')
    group.add_argument('--untie-embeddings-and-output-weights', action='store_true',
                       help='Untie embeddings and output weights.'),
    return parser


def _add_straggler_detector_args(parser):
    group = parser.add_argument_group(title='straggler')
    group.add_argument('--log-straggler', action='store_true',
                       help='If set, tracks and logs straggler per GPU.')
    group.add_argument('--disable-straggler-on-startup', action='store_true',
                       help='If set, StragglerDetector is disabled on startup.')
    group.add_argument('--straggler-ctrlr-port', type=int, default=65535,
                       help='Port number to toggle StragglerDetector on/off at runtime')
    group.add_argument('--straggler-minmax-count', type=int, default=1,
                       help='Number of ranks to report with high/low estimated throughput')
    return parser


def _add_logging_args(parser):
    group = parser.add_argument_group(title='logging')

    group.add_argument('--log-params-norm', action='store_true',
                       help='If set, calculate and log parameters norm.')
    group.add_argument('--log-num-zeros-in-grad', action='store_true',
                       help='If set, calculate and log the number of zeros in gradient.')
    group.add_argument('--log-throughput', action='store_true',
                       help='If set, calculate and log throughput per GPU.')
    group.add_argument('--log-progress', action='store_true',
                       help='If set, log progress (in terms of number of processed tokens and '
                       'number of floating-point operations) to progress.txt file in checkpoint '
                       'directory.')
    group.add_argument('--timing-log-level', type=int,
                       default=0, choices=range(0,3),
                       help='Granularity level to measure and report timing. '
                       '   0: report only iteration time and make sure timing '
                       '      does not introduce extra overhead.'
                       '   1: report timing for operations that are executed '
                       '      very limited times (basically once) during '
                       '      each iteration (such as gradient all-reduce) '
                       '   2: report timing for operations that migh be '
                       '      executed numerous times during each iteration. '
                       'Note that setting the level to 1 or 2 might '
                       'cause increase in iteration time.')
    group.add_argument('--no-barrier-with-level-1-timing', action='store_false',
                       help='If not set, use barrier with level 1 time '
                       'measurements. Note that this is up to the user '
                       'to make sure calling barrier with their timers '
                       'will not result in hangs. This can happen if for '
                       'example the user adds a level 1 timer that is not '
                       'called by all ranks.',
                       dest='barrier_with_L1_time')
    group.add_argument('--timing-log-option', type=str, default='minmax',
                       choices=['max', 'minmax', 'all'],
                       help='Options for logging timing:'
                       '  max: report the max timing across all ranks'
                       '  minmax: report min and max timings across all ranks'
                       '  all: report timings of all ranks.')
    group.add_argument('--tensorboard-log-interval', type=int, default=1,
                       help='Report to tensorboard interval.')
    group.add_argument('--tensorboard-queue-size', type=int, default=1000,
                       help='Size of the tensorboard queue for pending events '
                       'and summaries before one of the ‘add’ calls forces a '
                       'flush to disk.')
    group.add_argument('--log-timers-to-tensorboard', action='store_true',
                       help='If set, write timers to tensorboard.')
    group.add_argument('--log-batch-size-to-tensorboard', action='store_true',
                       help='If set, write batch-size to tensorboard.')
    group.add_argument('--no-log-learnig-rate-to-tensorboard',
                       action='store_false',
                       help='Disable learning rate logging to tensorboard.',
                       dest='log_learning_rate_to_tensorboard')
    group.add_argument('--no-log-loss-scale-to-tensorboard',
                       action='store_false',
                       help='Disable loss-scale logging to tensorboard.',
                       dest='log_loss_scale_to_tensorboard')
    group.add_argument('--log-validation-ppl-to-tensorboard',
                       action='store_true',
                       help='If set, write validation perplexity to '
                       'tensorboard.')
    group.add_argument('--log-memory-to-tensorboard',
                       action='store_true',
                       help='Enable memory logging to tensorboard.')
    group.add_argument('--log-world-size-to-tensorboard',
                       action='store_true',
                       help='Enable world size logging to tensorboard.')
    group.add_argument('--wandb-project', type=str, default=None,
                       help='The wandb project name. Ignore wandb by default.')
    group.add_argument('--wandb-name', type=str, default=None,
                       help='The wandb experiment name.')
    group.add_argument('--wandb-save-dir', type=str, default='',
                       help='Path to save the wandb results locally.')
    group.add_argument("--use-mpi", action="store_true", default=False)
    group.add_argument('--wandb-entity', type=str, default=None)
    group.add_argument("--wandb-id", default=None)
    group.add_argument('--enable-one-logger', action='store_true',
                       help='If set, use one_logger to track E2E metrics'
                       'Note that one_logger is an internal tool and not available externally. '
                       'For installation, please try command: `pip install '
                       '--index-url=https://sc-hw-artf.nvidia.com/api/pypi/hwinf-ml-pypi/simple'
                       ' one_logger` or go to https://gitlab-master.nvidia.com/hwinf-dcm/onelogger '
                       'for more details')
    group.add_argument('--one-logger-project', type=str, default='e2e-tracking',
                       help='The one-logger project name. Will ignore if '
                       '--enable-one-logger is not set')
    group.add_argument('--one-logger-entity', type=str, default='hwinf_dcm',
                       help='The one-logger username or team name. Will ignore if '
                       '--enable-one-logger is not set')
    group.add_argument('--one-logger-run-name', type=str, default=None,
                       help='The one-logger run name displayed. Will ignore if '
                       '--enable-one-logger is not set')
    return parser


def _add_regularization_args(parser):
    group = parser.add_argument_group(title='regularization')

    group.add_argument('--attention-dropout', type=float, default=0.1,
                       help='Post attention dropout probability.')
    group.add_argument('--hidden-dropout', type=float, default=0.1,
                       help='Dropout probability for hidden state transformer.')
    group.add_argument('--weight-decay', type=float, default=0.01,
                       help='Weight decay coefficient for L2 regularization.')
    group.add_argument('--start-weight-decay', type=float,
                       help='Initial weight decay coefficient for L2 regularization.')
    group.add_argument('--end-weight-decay', type=float,
                       help='End of run weight decay coefficient for L2 regularization.')
    group.add_argument('--weight-decay-incr-style', type=str, default='constant',
                       choices=['constant', 'linear', 'cosine'],
                       help='Weight decay increment function.')
    group.add_argument('--clip-grad', type=float, default=1.0,
                       help='Gradient clipping based on global L2 norm.')
    group.add_argument('--adam-beta1', type=float, default=0.9,
                       help='First coefficient for computing running averages '
                       'of gradient and its square')
    group.add_argument('--adam-beta2', type=float, default=0.999,
                       help='Second coefficient for computing running averages '
                       'of gradient and its square')
    group.add_argument('--adam-eps', type=float, default=1e-08,
                       help='Term added to the denominator to improve'
                       'numerical stability')
    group.add_argument('--sgd-momentum', type=float, default=0.9,
                       help='Momentum factor for sgd')
    return parser


def _add_training_args(parser):
    group = parser.add_argument_group(title='training')

    group.add_argument('--micro-batch-size', type=int, default=None,
                       help='Batch size per model instance (local batch size). '
                       'Global batch size is local batch size times data '
                       'parallel size times number of micro batches.')
    group.add_argument('--batch-size', type=int, default=None,
                       help='Old batch size parameter, do not use. '
                       'Use --micro-batch-size instead')
    group.add_argument('--global-batch-size', type=int, default=None,
                       help='Training batch size. If set, it should be a '
                       'multiple of micro-batch-size times data-parallel-size. '
                       'If this value is None, then '
                       'use micro-batch-size * data-parallel-size as the '
                       'global batch size. This choice will result in 1 for '
                       'number of micro-batches.')
    group.add_argument('--rampup-batch-size', nargs='*', default=None,
                       help='Batch size ramp up with the following values:'
                       '  --rampup-batch-size <start batch size> '
                       '                      <batch size incerement> '
                       '                      <ramp-up samples> '
                       'For example:'
                       '   --rampup-batch-size 16 8 300000 \ '
                       '   --global-batch-size 1024'
                       'will start with global batch size 16 and over '
                       ' (1024 - 16) / 8 = 126 intervals will increase'
                       'the batch size linearly to 1024. In each interval'
                       'we will use approximately 300000 / 126 = 2380 samples.')
    group.add_argument('--recompute-activations', action='store_true',
                       help='recompute activation to allow for training '
                       'with larger models, sequences, and batch sizes.')
    group.add_argument('--recompute-granularity', type=str, default=None,
                       choices=['full', 'selective'],
                       help='Checkpoint activations to allow for training '
                       'with larger models, sequences, and batch sizes. '
                       'It is supported at two granularities 1) full: '
                       'whole transformer layer is recomputed, '
                       '2) selective: core attention part of the transformer '
                       'layer is recomputed.')
    group.add_argument('--no-check-for-nan-in-loss-and-grad', action='store_false',
                       help='Check for NaNs in loss and grad',
                       dest='check_for_nan_in_loss_and_grad')
    group.add_argument('--distribute-saved-activations',
                       action='store_true',
                       help='If set, distribute recomputed activations '
                       'across model parallel group.')
    group.add_argument('--recompute-method', type=str, default=None,
                       choices=['uniform', 'block'],
                       help='1) uniform: uniformly divide the total number of '
                       'Transformer layers and recompute the input activation of '
                       'each divided chunk at specified granularity, '
                       '2) recompute the input activations of only a set number of '
                       'individual Transformer layers per pipeline stage and do the '
                       'rest without any recomputing at specified granularity'
                       'default) do not apply activations recompute to any layers')
    group.add_argument('--recompute-num-layers', type=int, default=None,
                       help='1) uniform: the number of Transformer layers in each '
                       'uniformly divided recompute unit, '
                       '2) block: the number of individual Transformer layers '
                       'to recompute within each pipeline stage.')
    group.add_argument('--no-clone-scatter-output-in-embedding', action='store_false',
                       help='If not set, clone the output of the scatter in embedding layer to GC original tensor.',
                       dest='clone_scatter_output_in_embedding')
    group.add_argument('--profile', action='store_true',
                       help='Enable nsys profiling. When using this option, nsys '
                       'options should be specified in commandline. An example '
                       'nsys commandline is `nsys profile -s none -t nvtx,cuda '
                       '-o <path/to/output_file> --force-overwrite true '
                       '--capture-range=cudaProfilerApi '
                       '--capture-range-end=stop`.')
    group.add_argument('--profile-step-start', type=int, default=10,
                       help='Global step to start profiling.')
    group.add_argument('--profile-step-end', type=int, default=12,
                       help='Global step to stop profiling.')
    group.add_argument('--profile-ranks', nargs='+', type=int, default=[0],
                       help='Global ranks to profile.')
    group.add_argument('--tp-comm-overlap', action='store_true', help='Enables the '
                       ' overlap of Tensor parallel communication and GEMM kernels.')
    group.add_argument('--tp-comm-overlap-cfg', type=str, default=None,
                       help='Config file when tp_comm_overlap is enabled.')
    group.add_argument('--disable-tp-comm-overlap-ag', action='store_false', 
                       help=('Disables the All-Gather overlap with GEMM by '
                             'pipelining the GEMM and All-Gather.'),
                       dest='tp_comm_overlap_ag')
    group.add_argument('--disable-tp-comm-overlap-rs', action='store_false',
                       help=('Disables the Reduce-Scatter overlap with GEMM by '
                             'pipelining the GEMM and Reduce-Scatter.'),
                       dest='tp_comm_overlap_rs')
    group.add_argument('--tp-comm-overlap-rs-dgrad', action='store_true',
                       help = 'Enables the Reduce-Scatter overlap with dgrad GEMM.',
                       dest='tp_comm_overlap_rs_dgrad')
    group.add_argument('--disable-tp-comm-bulk-dgrad', action='store_false',
                       help='Disables the All-Gather overlap with bprop activation gradient GEMM.',
                       dest='tp_comm_bulk_dgrad')
    group.add_argument('--disable-tp-comm-bulk-wgrad', action='store_false',
                       help='Disables the Reduce-Scatter overlap with bprop weight gradient GEMM.',
                       dest='tp_comm_bulk_wgrad')
    group.add_argument('--use-cpu-initialization', action='store_true',
                       default=None,
                       help='If set, initialize weights on the CPU. This eliminates init differences based on tensor parallelism.')
    group.add_argument('--empty-unused-memory-level', default=0, type=int,
                       choices=[0, 1, 2],
                       help='Call torch.cuda.empty_cache() each iteration '
                       '(training and eval), to reduce fragmentation.'
                       '0=off, 1=moderate, 2=aggressive.')

    # deprecated
    group.add_argument('--checkpoint-activations', action='store_true',
                       help='Checkpoint activation to allow for training '
                       'with larger models, sequences, and batch sizes.')
    group.add_argument('--train-iters', type=int, default=None,
                       help='Total number of iterations to train over all '
                       'training runs. Note that either train-iters or '
                       'train-samples should be provided.')
    group.add_argument('--train-samples', type=int, default=None,
                       help='Total number of samples to train over all '
                       'training runs. Note that either train-iters or '
                       'train-samples should be provided.')
    group.add_argument('--log-interval', type=int, default=100,
                       help='Report loss and timing interval.')
    group.add_argument('--exit-interval', type=int, default=None,
                       help='Exit the program after the iteration is divisible '
                       'by this value.')
    group.add_argument('--exit-duration-in-mins', type=int, default=None,
                       help='Exit the program after this many minutes.')
    group.add_argument('--exit-signal-handler', action='store_true',
                       help='Dynamically save the checkpoint and shutdown the '
                       'training if SIGTERM is received')
    group.add_argument('--tensorboard-dir', type=str, default=None,
                       help='Write TensorBoard logs to this directory.')
    group.add_argument('--no-masked-softmax-fusion',
                       action='store_false',
                       help='Disable fusion of query_key_value scaling, '
                       'masking, and softmax.',
                       dest='masked_softmax_fusion')
    group.add_argument('--no-bias-gelu-fusion', action='store_false',
                       help='Disable bias and gelu fusion.',
                       dest='bias_gelu_fusion')
    group.add_argument('--no-bias-swiglu-fusion', action='store_false',
                       help='Disable bias and swiglu fusion, the fusion is '
                       'available only when using megatron-core.',
                       dest='bias_swiglu_fusion')
    group.add_argument('--no-bias-dropout-fusion', action='store_false',
                       help='Disable bias and dropout fusion.',
                       dest='bias_dropout_fusion')
    group.add_argument('--no-rope-fusion', action='store_false',
                       help='Disable rope fusion, the fusion is available '
                       'only when using megatron-core.',
                       dest='apply_rope_fusion')
    group.add_argument('--use-flash-attn', action='store_true',
                       help='use FlashAttention implementation of attention. '
                       'https://arxiv.org/abs/2205.14135')
    group.add_argument('--disable-bias-linear', action='store_false',
                       help='Disable bias in the linear layers',
                       dest='add_bias_linear')
    group.add_argument('--add-qkv-bias', action='store_true',
                       help='Enable bias only in the QKV linear layers',
                       dest='add_qkv_bias')
    group.add_argument('--optimizer', type=str, default='adam',
                       choices=['adam', 'sgd'],
                       help='Optimizer function')
    group.add_argument('--dataloader-type', type=str, default=None,
                       choices=['single', 'cyclic', 'external'],
                       help='Single pass vs multiple pass data loader')
    group.add_argument('--no-async-tensor-model-parallel-allreduce',
                       action='store_false',
                       help='Disable asynchronous execution of '
                       'tensor-model-parallel all-reduce with weight '
                       'gradient compuation of a column-linear layer.',
                       dest='async_tensor_model_parallel_allreduce')
    group.add_argument('--no-persist-layer-norm', action='store_true',
                       help='Disable using persistent fused layer norm kernel. '
                       'This kernel supports only a set of hidden sizes. Please '
                       'check persist_ln_hidden_sizes if your hidden '
                       'size is supported.')
    group.add_argument('--sequence-parallel', action='store_true',
                       help='Enable sequence parallel optimization.')
    group.add_argument('--no-gradient-accumulation-fusion',
                       action='store_false',
                       help='Disable fusing gradient accumulation to weight '
                       'gradient computation of linear layers',
                       dest='gradient_accumulation_fusion')
    group.add_argument('--use-mcore-models', action='store_true',
                       help='Use the implementation from megatron core')
    group.add_argument('--manual-gc', action='store_true',
                       help='Disable the threshold-based default garbage '
                       'collector and trigger the garbage collection manually. '
                       'Manual garbage collection helps to align the timing of '
                       'the collection across ranks which mitigates the impact '
                       'of CPU-associated jitters. When the manual gc is enabled, '
                       'garbage collection is performed only at the start and the '
                       'end of the validation routine by default.')
    group.add_argument('--manual-gc-interval', type=int, default=0,
                       help='Training step interval to trigger manual garbage '
                       'collection. When the value is set to 0, garbage '
                       'collection is not triggered between training steps.')
    group.add_argument('--no-manual-gc-eval', action='store_false',
                       help='When using manual garbage collection, disable '
                       'garbage collection at the start and the end of each '
                       'evaluation run.', dest='manual_gc_eval')
    group.add_argument('--disable-tp-comm-split-ag', action='store_false',
                       help='Disables the All-Gather overlap with fprop GEMM.',
                       dest='tp_comm_split_ag')
    group.add_argument('--disable-tp-comm-split-rs', action='store_false',
                       help='Disables the Reduce-Scatter overlap with fprop GEMM.',
                       dest='tp_comm_split_rs')
    group.add_argument('--skip-train-iteration-range', type=str, nargs='+', default=None,
                       help='Iteration ranges to skip. The values are one or more dash-separated ranges. e.g., 101-200 251-300.')
    group.add_argument("--use-z-loss", action="store_true", help="use z-loss for supplement loss (Google PaLM method)")

    return parser


def _add_initialization_args(parser):
    group = parser.add_argument_group(title='initialization')

    group.add_argument('--seed', type=int, default=1234,
                       help='Random seed used for python, numpy, '
                       'pytorch, and cuda.')
    group.add_argument('--data-parallel-random-init', action='store_true',
                       help='Enable random initialization of params '
                       'across data parallel ranks')
    group.add_argument('--init-method-std', type=float, default=0.02,
                       help='Standard deviation of the zero mean normal '
                       'distribution used for weight initialization.')
    group.add_argument('--init-method-xavier-uniform', action='store_true',
                       help='Enable Xavier uniform parameter initialization')

    return parser


def _add_learning_rate_args(parser):
    group = parser.add_argument_group(title='learning rate')

    group.add_argument('--lr', type=float, default=None,
                       help='Initial learning rate. Depending on decay style '
                       'and initial warmup, the learning rate at each '
                       'iteration would be different.')
    group.add_argument('--lr-decay-style', type=str, default='linear',
                       choices=['constant', 'linear', 'cosine', 'inverse-square-root'],
                       help='Learning rate decay function.')
    group.add_argument('--lr-decay-iters', type=int, default=None,
                       help='number of iterations to decay learning rate over,'
                       ' If None defaults to `--train-iters`')
    group.add_argument('--lr-decay-samples', type=int, default=None,
                       help='number of samples to decay learning rate over,'
                       ' If None defaults to `--train-samples`')
    group.add_argument('--lr-warmup-fraction', type=float, default=None,
                       help='fraction of lr-warmup-(iters/samples) to use '
                       'for warmup (as a float)')
    group.add_argument('--lr-warmup-iters', type=int, default=0,
                       help='number of iterations to linearly warmup '
                       'learning rate over.')
    group.add_argument('--lr-warmup-samples', type=int, default=0,
                       help='number of samples to linearly warmup '
                       'learning rate over.')
    group.add_argument('--lr-warmup-init', type=float, default=0.0,
                       help='Initial value for learning rate warmup. The '
                       'scheduler starts warmup from this value.')
    group.add_argument('--warmup', type=int, default=None,
                       help='Old lr warmup argument, do not use. Use one of the'
                       '--lr-warmup-* arguments above')
    group.add_argument('--min-lr', type=float, default=0.0,
                       help='Minimum value for learning rate. The scheduler'
                       'clip values below this threshold.')
    group.add_argument('--override-opt_param-scheduler', action='store_true',
                       help='Reset the values of the scheduler (learning rate,'
                       'warmup iterations, minimum learning rate, maximum '
                       'number of iterations, and decay style from input '
                       'arguments and ignore values from checkpoints. Note'
                       'that all the above values will be reset.')
    group.add_argument('--use-checkpoint-opt_param-scheduler', action='store_true',
                       help='Use checkpoint to set the values of the scheduler '
                       '(learning rate, warmup iterations, minimum learning '
                       'rate, maximum number of iterations, and decay style '
                       'from checkpoint and ignore input arguments.')
    group.add_argument('--decoupled-lr', type=float, default=None,
                       help='Separate learning rate for the input and output layer')
    group.add_argument('--decoupled-min-lr', type=float, default=None,
                       help='Minimum value for learning rate for the input and output layer. The scheduler'
                       'clip values below this threshold')

    return parser


def _add_checkpointing_args(parser):
    group = parser.add_argument_group(title='checkpointing')

    group.add_argument('--save', type=str, default=None,
                       help='Output directory to save checkpoints to.')
    group.add_argument('--save-interval', type=int, default=None,
                       help='Number of iterations between checkpoint saves.')
    group.add_argument('--no-save-optim', action='store_true', default=None,
                       help='Do not save current optimizer.')
    group.add_argument('--no-save-rng', action='store_true', default=None,
                       help='Do not save current rng state.')
    group.add_argument('--load', type=str, default=None,
                       help='Directory containing a model checkpoint.')
    group.add_argument('--no-load-optim', action='store_true', default=None,
                       help='Do not load optimizer when loading checkpoint.')
    group.add_argument('--no-load-rng', action='store_true', default=None,
                       help='Do not load rng state when loading checkpoint.')
    group.add_argument('--finetune', action='store_true',
                       help='Load model for finetuning. Do not load optimizer '
                       'or rng state from checkpoint and set iteration to 0. '
                       'Assumed when loading a release checkpoint.')
    group.add_argument('--pretrained-checkpoint', type=str, default=None,
                       help='Directory containing a pretrained model checkpoint for finetuning.')
    group.add_argument('--ckpt-step', type=int, default=None,
                       help='Checkpoint step to load model from.')
    group.add_argument('--no-initialization', action='store_false',
                       help='Do not perform initialization when building model, '
                       'can reduce startup time when definitely loading from a '
                       'checkpoint',
                       dest='perform_initialization')
    group.add_argument('--use-checkpoint-args', action='store_true',
                       help='Override any command line arguments with arguments '
                       'from the checkpoint')
    group.add_argument('--exit-on-missing-checkpoint', action='store_true',
                       help="If '--load' is set, but checkpoint is not found "
                       "(e.g., path typo), then exit instead of random "
                       "initialization.")
    group.add_argument('--use-dist-ckpt', action='store_true',
                       help='Use distributed checkpoint format.')
    group.add_argument('--auto-detect-ckpt-format', action='store_true',
                       help='Determine if the checkpoint format is in legacy or distributed format.'
                            ' If False, expects distributed checkpoint iff args.use_dist_ckpt.'
                            ' Might slow down loading a bit (double rank0 ckpt load).')
    group.add_argument('--dist-ckpt-format', type=str, default='torch_dist',
                       choices=['zarr', 'torch_dist'],
                       help='Distributed checkpoint format to use.')
    group.add_argument('--ckpt-fully-parallel-save', action='store_true',
                       help='Apply full save parallelization across DP for'
                            ' distributed checkpoints. Depending on ckpt format'
                            ' might increase number of files in the checkpoint.')
    group.add_argument('--use-gcp-dynamic-checkpointing', action='store_true')
    group.add_argument('--dynamic-checkpointing-min', type=int, default=0)

    return parser


def _add_mixed_precision_args(parser):
    group = parser.add_argument_group(title='mixed precision')

    group.add_argument('--fp16', action='store_true',
                       help='Run model in fp16 mode.')
    group.add_argument('--bf16', action='store_true',
                       help='Run model in bfloat16 mode.')
    group.add_argument('--loss-scale', type=float, default=None,
                       help='Static loss scaling, positive power of 2 '
                       'values can improve fp16 convergence. If None, dynamic'
                       'loss scaling is used.')
    group.add_argument('--initial-loss-scale', type=float, default=2**32,
                       help='Initial loss-scale for dynamic loss scaling.')
    group.add_argument('--min-loss-scale', type=float, default=1.0,
                       help='Minimum loss scale for dynamic loss scaling.')
    group.add_argument('--loss-scale-window', type=float, default=1000,
                       help='Window over which to raise/lower dynamic scale.')
    group.add_argument('--hysteresis', type=int, default=2,
                       help='hysteresis for dynamic loss scaling')
    group.add_argument('--fp32-residual-connection', action='store_true',
                       help='Move residual connections to fp32.')
    group.add_argument('--apply-query-key-layer-scaling', action='store_true',
                       help='Scale Q * K^T by 1 / layer-number. '
                       'Useful for fp16 training.')
    group.add_argument('--attention-softmax-in-fp32', action='store_true',
                       help='Run attention masking and softmax in fp32. '
                       'This flag is ignored unless '
                       '--no-query-key-layer-scaling is specified.')
    group.add_argument('--accumulate-allreduce-grads-in-fp32',
                       action='store_true',
                       help='Gradient accumulation and all-reduce in fp32.')
    group.add_argument('--fp16-lm-cross-entropy', action='store_true',
                       help='Move the cross entropy unreduced loss calculation'
                       'for lm head to fp16.')

    return parser


def _add_distributed_args(parser):
    group = parser.add_argument_group(title='distributed')

    group.add_argument('--tensor-model-parallel-size', type=int, default=1,
                       help='Degree of tensor model parallelism.')
    group.add_argument('--pipeline-model-parallel-size', type=int, default=1,
                       help='Degree of pipeline model parallelism.')
    group.add_argument('--pipeline-model-parallel-split-rank',
                       type=int, default=None,
                       help='Rank where encoder and decoder should be split.')
    group.add_argument('--model-parallel-size', type=int, default=None,
                       help='Old model parallel argument, do not use. Use '
                       '--tensor-model-parallel-size instead.')
    group.add_argument('--num-layers-per-virtual-pipeline-stage', type=int, default=None,
                       help='Number of layers per virtual pipeline stage')
    group.add_argument('--no-overlap-p2p-communication', action='store_false',
                       help='overlap pipeline parallel communication with forward and backward chunks',
                       dest='overlap_p2p_comm')
    group.add_argument('--distributed-backend', default='nccl',
                       choices=['nccl', 'gloo'],
                       help='Which backend to use for distributed training.')
    group.add_argument('--distributed-timeout-minutes', type=int, default=10,
                       help='Timeout minutes for torch.distributed.')
    group.add_argument('--overlap-grad-reduce', action='store_true',
                       default=False, help='If set, overlap DDP grad reduce.')
    group.add_argument('--no-delay-grad-reduce', action='store_false',
                       help='If not set, delay / synchronize grad reductions in all but first PP stage.',
                       dest='delay_grad_reduce')
    group.add_argument('--ddp-bucket-size', type=int, default=None,
                       help='Bucket size for data-parallel communication')
    group.add_argument('--overlap-param-gather', action='store_true',
                       default=False, help='If set, overlap param all-gather in distributed optimizer.')
    group.add_argument('--delay-param-gather', action='store_true',
                       default=False, help='If set, delay / synchronize param all-gathers in all but first PP stage.')
    group.add_argument('--no-scatter-gather-tensors-in-pipeline', action='store_false',
                       help='If not set, use scatter/gather to optimize communication of tensors in pipeline.',
                       dest='scatter_gather_tensors_in_pipeline')
    group.add_argument('--use-ring-exchange-p2p', action='store_true',
                       default=False, help='If set, use custom-built ring exchange '
                       'for p2p communications. Note that this option will require '
                       'a custom built image that support ring-exchange p2p.')
    group.add_argument('--local_rank', type=int, default=None,
                       help='local rank passed from distributed launcher.')
    group.add_argument('--lazy-mpu-init', type=bool, required=False,
                       help='If set to True, initialize_megatron() '
                       'skips DDP initialization and returns function to '
                       'complete it instead.Also turns on '
                       '--use-cpu-initialization flag. This is for '
                       'external DDP manager.' )
    group.add_argument('--standalone-embedding-stage', action='store_true',
                       default=False, help='If set, *input* embedding layer '
                       'is placed on its own pipeline stage, without any '
                       'transformer layers. (For T5, this flag currently only '
                       'affects the encoder embedding.)')
    group.add_argument('--use-distributed-optimizer', action='store_true',
                       help='Use distributed optimizer.')
    group.add_argument('--context-parallel-size', type=int, default=1,
                       help='Degree of context parallelism.')
    group.add_argument('--nccl-communicator-config-path', type=str, default=None,
                       help='Path to the yaml file with NCCL communicator '
                       'configurations. The number of min/max thread groups and thread '
                       'group cluster size of each communicator can be configured by '
                       'setting `min_ctas`, `max_ctas`, and `cga_cluster_size`.')
    group.add_argument('--use-tp-pp-dp-mapping', action='store_true', default=False,
                        help='If set, distributed ranks initialize order is changed '
                        'from tp-dp-pp to tp-pp-dp. Make sure EP and CP aren\'t used '
                        'with this option enabled')
    return parser


def _add_validation_args(parser):
    group = parser.add_argument_group(title='validation')

    group.add_argument('--eval-iters', type=int, default=100,
                       help='Number of iterations to run for evaluation'
                       'validation/test for.')
    group.add_argument('--eval-interval', type=int, default=1000,
                       help='Interval between running evaluation on '
                       'validation set.')
    group.add_argument("--test-mode", action="store_true", help='Run all real-time test alongside the experiment.')
    group.add_argument('--skip-train', action='store_true',
                       default=False, help='If set, bypass the training loop, '
                       'optionally do evaluation for validation/test, and exit.')

    return parser


def _add_data_args(parser):
    group = parser.add_argument_group(title='data and dataloader')

    group.add_argument('--data-path', nargs='*', default=None,
                       help='Path to the training dataset. Accepted format:'
                       '1) a single data path, 2) multiple datasets in the'
                       'form: dataset1-weight dataset1-path dataset2-weight '
                       'dataset2-path ... It is used with --split when a '
                       'single dataset used for all three: train, valid '
                       'and test. It is exclusive to the other '
                       '--*-data-path args')
    group.add_argument('--split', type=str, default='969, 30, 1',
                       help='Comma-separated list of proportions for training,'
                       ' validation, and test split. For example the split '
                       '`90,5,5` will use 90%% of data for training, 5%% for '
                       'validation and 5%% for test.')
    group.add_argument('--train-data-path', nargs='*', default=None,
                       help='Path to the training dataset. Accepted format:'
                       '1) a single data path, 2) multiple datasets in the'
                       'form: dataset1-weight dataset1-path dataset2-weight '
                       'dataset2-path ...')
    group.add_argument('--valid-data-path', nargs='*', default=None,
                       help='Path to the validation dataset. Accepted format:'
                       '1) a single data path, 2) multiple datasets in the'
                       'form: dataset1-weight dataset1-path dataset2-weight '
                       'dataset2-path ...')
    group.add_argument('--test-data-path', nargs='*', default=None,
                       help='Path to the test dataset. Accepted format:'
                       '1) a single data path, 2) multiple datasets in the'
                       'form: dataset1-weight dataset1-path dataset2-weight '
                       'dataset2-path ...')
    group.add_argument('--data-cache-path', default=None,
                       help='Path to a directory to hold cached index files.')
    group.add_argument('--no-mmap-bin-files', action='store_false',
                       help='Disable mmap-ing of .bin files.',
                       dest='mmap_bin_files')
    group.add_argument('--mock-data', action='store_true',
                       help='Skip data loading and validation and opt for artificial '
                       'generation of mock data when an implementation is available.')

    group.add_argument('--vocab-size', type=int, default=None,
                       help='Size of vocab before EOD or padding.')
    group.add_argument('--vocab-file', type=str, default=None,
                       help='Path to the vocab file.')
    group.add_argument('--merge-file', type=str, default=None,
                       help='Path to the BPE merge file.')
    group.add_argument('--vocab-extra-ids', type=int, default=0,
                       help='Number of additional vocabulary tokens. '
                            'They are used for span masking in the T5 model')
    group.add_argument('--seq-length', type=int, default=None,
                       help='Maximum sequence length to process.')
    group.add_argument('--encoder-seq-length', type=int, default=None,
                       help='Maximum encoder sequence length to process.'
                       'This should be exclusive of --seq-length')
    group.add_argument('--decoder-seq-length', type=int, default=None,
                       help="Maximum decoder sequence length to process.")
    group.add_argument('--retriever-seq-length', type=int, default=256,
                       help='Maximum sequence length for the biencoder model '
                       'for retriever')
    group.add_argument('--sample-rate', type=float, default=1.0,
                       help='sample rate for training data. Supposed to be 0 '
                            ' < sample_rate < 1')
    group.add_argument('--mask-prob', type=float, default=0.15,
                       help='Probability of replacing a token with mask.')
    group.add_argument('--short-seq-prob', type=float, default=0.1,
                       help='Probability of producing a short sequence.')
    group.add_argument('--num-workers', type=int, default=2,
                       help="Dataloader number of workers.")
    group.add_argument('--tokenizer-type', type=str,
                       default=None,
                       choices=['BertWordPieceLowerCase',
                                'BertWordPieceCase',
                                'GPT2BPETokenizer',
                                'SentencePieceTokenizer',
                                'GPTSentencePieceTokenizer',
                                'Llama2Tokenizer',
                                'Llama3Tokenizer',
                                'NullTokenizer'],
                       help='What type of tokenizer to use.')
    group.add_argument('--tokenizer-model', type=str, default=None,
                       help='Sentencepiece tokenizer model.')
    group.add_argument('--reset-position-ids', action='store_true',
                       help='Reset posistion ids after end-of-document token.')
    group.add_argument('--reset-attention-mask', action='store_true',
                       help='Reset self attention maske after '
                       'end-of-document token.')
    group.add_argument('--eod-mask-loss', action='store_true',
                       help='Mask loss for the end of document tokens.')
    group.add_argument('--no-create-attention-mask-in-dataloader', action='store_false',
                       help='If set, do not create attention_masks in dataloader.',
                       dest='create_attention_mask_in_dataloader')

    return parser


def _add_autoresume_args(parser):
    group = parser.add_argument_group(title='autoresume')

    group.add_argument('--adlr-autoresume', action='store_true',
                       help='Enable autoresume on adlr cluster.')
    group.add_argument('--adlr-autoresume-interval', type=int, default=1000,
                       help='Intervals over which check for autoresume'
                       'termination signal')

    return parser


def _add_biencoder_args(parser):
    group = parser.add_argument_group(title='biencoder')

    # network size
    group.add_argument('--ict-head-size', type=int, default=None,
                       help='Size of block embeddings to be used in ICT and '
                        'REALM (paper default: 128)')
    group.add_argument('--biencoder-projection-dim', type=int, default=0,
                       help='Size of projection head used in biencoder (paper'
                        ' default: 128)')
    group.add_argument('--biencoder-shared-query-context-model', action='store_true',
                        help='Whether to share the parameters of the query '
                        'and context models or not')

    # checkpointing
    group.add_argument('--ict-load', type=str, default=None,
                       help='Directory containing an ICTBertModel checkpoint')
    group.add_argument('--bert-load', type=str, default=None,
                       help='Directory containing an BertModel checkpoint '
                       '(needed to start ICT and REALM)')

    # data
    group.add_argument('--titles-data-path', type=str, default=None,
                       help='Path to titles dataset used for ICT')
    group.add_argument('--query-in-block-prob', type=float, default=0.1,
                       help='Probability of keeping query in block for '
                       'ICT dataset')
    group.add_argument('--use-one-sent-docs', action='store_true',
                       help='Whether to use one sentence documents in ICT')
    group.add_argument('--evidence-data-path', type=str, default=None,
                       help='Path to Wikipedia Evidence frm DPR paper')

    # training
    group.add_argument('--retriever-report-topk-accuracies', nargs='+', type=int,
                        default=[], help="Which top-k accuracies to report "
                        "(e.g. '1 5 20')")
    group.add_argument('--retriever-score-scaling', action='store_true',
                       help='Whether to scale retriever scores by inverse '
                        'square root of hidden size')

    # faiss index
    group.add_argument('--block-data-path', type=str, default=None,
                       help='Where to save/load BlockData to/from')
    group.add_argument('--embedding-path', type=str, default=None,
                       help='Where to save/load Open-Retrieval Embedding'
                        ' data to/from')

    # indexer
    group.add_argument('--indexer-batch-size', type=int, default=128,
                       help='How large of batches to use when doing indexing '
                       'jobs')
    group.add_argument('--indexer-log-interval', type=int, default=1000,
                       help='After how many batches should the indexer '
                       'report progress')
    return parser


def _add_vision_args(parser):
    group = parser.add_argument_group(title="vision")

    # general vision arguements
    group.add_argument('--num-classes', type=int, default=1000,
                       help='num of classes in vision classificaiton task')
    group.add_argument('--img-h', type=int, default=224,
                       help='Image height for vision classification task')
    group.add_argument('--img-w', type=int, default=224,
                       help='Image height for vision classification task')
    group.add_argument('--num-channels', type=int, default=3,
                       help='Number of channels in input image data')
    group.add_argument('--patch-dim', type=int, default=16,
                       help='patch dimension')
    group.add_argument('--classes-fraction', type=float, default=1.0,
                       help='training with fraction of classes.')
    group.add_argument('--data-per-class-fraction', type=float, default=1.0,
                       help='training with fraction of data per class.')
    group.add_argument('--no-data-sharding', action='store_false',
                       help='Disable data sharding.',
                       dest='data_sharding')
    group.add_argument('--head-lr-mult', type=float, default=1.0,
                       help='learning rate multiplier for head during finetuning')

    # pretraining type and backbone selection`
    group.add_argument('--vision-pretraining', action='store_true',
                       help='flag to indicate vision pretraining')
    group.add_argument('--vision-pretraining-type', type=str, default='classify',
                       choices=['classify', 'inpaint', 'dino'],
                       help='pretraining objectives')
    group.add_argument('--vision-backbone-type', type=str, default='vit',
                       choices=['vit', 'mit', 'swin'],
                       help='backbone types types')
    group.add_argument('--swin-backbone-type', type=str, default='tiny',
                       choices=['tiny', 'base', 'h3'],
                       help='pretraining objectives')
    # inpainting arguments
    group.add_argument('--mask-type', type=str, default='random',
                       choices=['random', 'row'],
                       help='mask types')
    group.add_argument('--mask-factor', type=float, default=1.0,
                       help='mask size scaling parameter')

    # dino arguments
    group.add_argument('--iter-per-epoch', type=int, default=1250,
                       help='iterations per epoch')
    group.add_argument('--dino-local-img-size', type=int, default=96,
                       help='Image size for vision classification task')
    group.add_argument('--dino-local-crops-number', type=int, default=10,
                       help='Number of local crops')
    group.add_argument('--dino-head-hidden-size', type=int, default=2048,
                       help='Hidden dimension size in dino head')
    group.add_argument('--dino-bottleneck-size', type=int, default=256,
                       help='Bottle neck dimension in dino head ')
    group.add_argument('--dino-freeze-last-layer', type=float, default=1,
                       help='Freezing last layer weights')
    group.add_argument('--dino-norm-last-layer', action='store_true',
                       help='Disable Norm in last layer.')
    group.add_argument('--dino-warmup-teacher-temp', type=float, default=0.04,
                       help='warump teacher temperature')
    group.add_argument('--dino-teacher-temp', type=float, default=0.07,
                       help='teacher temperature')
    group.add_argument('--dino-warmup-teacher-temp-epochs', type=int, default=30,
                       help='warmup teacher temperaure epochs')

    # regularization arguments
    group.add_argument('--qk-layernorm', action='store_true',
                       help='Whether to layer normalize the q and k attention embeddings.')

    return parser

def _add_moe_args(parser):
    group = parser.add_argument_group(title="moe")
    group.add_argument('--expert-model-parallel-size', type=int, default=1,
                       help='Degree of expert model parallelism.')
    group.add_argument('--num-experts', type=int, default=None,
                       help='Number of Experts in MoE (None means no MoE)')
    group.add_argument('--moe-router-load-balancing-type', type=str,
                       choices=['aux_loss', 'sinkhorn', "none"],
                       default='aux_loss',
                       help='Determines the load balancing strategy for the router. "aux_loss" corresponds to the load balancing loss used in GShard and SwitchTransformer, "sinkhorn" corresponds to the balancing algorithm used in S-BASE, and "none" implies no load balancing. The default is "aux_loss".')
    group.add_argument('--moe-router-topk', type=int, default=2,
                       help='Number of experts to route to for each token. The default is 2.')
    group.add_argument('--moe-grouped-gemm', action='store_true',
                       help='When there are multiple experts per rank, compress multiple local (potentially small) gemms in a single kernel launch to improve the utilization and performance by leveraging the Grouped GEMM feature introduced since CUTLASS 2.8 (https://github.com/fanshiqing/grouped_gemm).')
    group.add_argument('--moe-aux-loss-coeff', type=float, default=0.0,
                       help='Scaling coefficient for the aux loss: a starting value of 1e-2 is recommended.')
    group.add_argument('--moe-z-loss-coeff', type=float, default=None,
                       help='Scaling coefficient for the z-loss: a starting value of 1e-3 is recommended.')
    group.add_argument('--moe-input-jitter-eps', type=float, default=None,
                       help='Add noise to the input tensor by applying jitter with a specified epsilon value.')
    group.add_argument('--moe-token-dropping', action='store_true',
                       help='This feature involves selectively dropping and padding tokens for each expert to achieve a specified capacity, similar to GShard, Switch-Transformer, and DeepSpeed-MoE. Note: Currently unsupported.')
    group.add_argument('--moe-token-dispatcher-type', type=str,
                       choices=['allgather', 'alltoall'],
                       default='allgather',
                       help='.')
    group.add_argument('--moe-per-layer-logging', action='store_true',
                       help='Enable per-layer logging for MoE, currently supports auxiliary loss and z loss.')

    return parser

def _add_experimental_args(parser):
    group = parser.add_argument_group(title='experimental')

    group.add_argument('--spec', type=str, default=None, nargs='*',
                       help='Specify the <module_location function_name> pair '
                       'that returns a spec to customize a model, transformer '
                       'block, or transformer layer, depending on the use case.'
                       'To use local spec specify local as the argument.'
                       'For more details, see the model class, '
                       '`transformer_block.py`, or `transformer_layer.py`')
    group.add_argument('--yaml-cfg', type=str, default=None,
                       help = 'Config file to add additional arguments')

    return parser