ColossalAI/colossalai/nn/parallel/gemini_parallel.py

40 lines
1.7 KiB
Python

import torch
from colossalai.gemini.chunk import init_chunk_manager
from colossalai.gemini.gemini_mgr import GeminiManager
from .data_parallel import ZeroDDP
class GeminiDDP(ZeroDDP):
def __init__(self,
module: torch.nn.Module,
device: torch.device,
placement_policy: str = "cpu",
pin_memory: bool = False,
force_outputs_fp32: bool = False,
search_range_mb: int = 32) -> None:
"""
A torch.Module warpper using ZeRODPP and Genimi.
ZeRO is for parallel. Gemini is for memory management.
Example:
model is initialized under the context of ColoInitContext
>>> model = GeminiDDP(model, torch.cuda.current_device(), "cuda")
>>> logits = model(x)
>>> loss = criterion(logits, labels)
>>> model.backward(loss)
Args:
module (torch.nn.Module): the model to be wrapped.
device (torch.device): device to place the model.
placement_policy (str, optional): "cpu", "cuda", "auto". Defaults to "cpu".
pin_memory (bool, optional): use pin memory on CPU. Defaults to False.
force_outputs_fp32 (bool, optional): force outputs are fp32. Defaults to False.
search_range_mb (int, optional): chunk size searching range in MegaByte. Defaults to 32.
"""
chunk_manager = init_chunk_manager(model=module, init_device=device, search_range_mb=search_range_mb)
gemini_manager = GeminiManager(placement_policy, chunk_manager, module)
super().__init__(module, gemini_manager, pin_memory, force_outputs_fp32)