distributed_config.py

# SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
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# Licensed under the Apache License, Version 2.0 (the "License");
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#     http://www.apache.org/licenses/LICENSE-2.0
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import logging
import os
from dataclasses import dataclass, field


logger = logging.getLogger(__name__)


@dataclass(frozen=True)
class DistributedConfig:
    """Class to track distributed ranks and handle basic distributed training setup.

    If torch distributed environment variables are not set, we set them to default values for single-process training.

    Attributes:
        rank: The rank of the process.
        local_rank: The local rank of the process.
        world_size: The total number of processes.
    """

    rank: int = field(default_factory=lambda: int(os.environ.setdefault("RANK", "0")))
    local_rank: int = field(default_factory=lambda: int(os.environ.setdefault("LOCAL_RANK", "0")))
    world_size: int = field(default_factory=lambda: int(os.environ.setdefault("WORLD_SIZE", "1")))
    _master_addr: str = field(default_factory=lambda: os.environ.setdefault("MASTER_ADDR", "localhost"))
    _master_port: str = field(default_factory=lambda: os.environ.setdefault("MASTER_PORT", "12355"))

    def is_main_process(self) -> bool:
        """This is the global rank 0 process, to be used for wandb logging, etc."""
        return self.rank == 0