Colossal-AI
An integrated large-scale model training system with efficient parallelization techniques.
Paper: Colossal-AI: A Unified Deep Learning System For Large-Scale Parallel Training
Blog: Colossal-AI: A Unified Deep Learning System For Large-Scale Parallel Training
Installation
PyPI
pip install colossalai
Install From Source
git clone git@github.com:hpcaitech/ColossalAI.git
cd ColossalAI
# install dependency
pip install -r requirements/requirements.txt
# install colossalai
pip install .
Install and enable CUDA kernel fusion (compulsory installation when using fused optimizer)
pip install -v --no-cache-dir --global-option="--cuda_ext" .
Documentation
Quick View
Start Distributed Training in Lines
import colossalai
from colossalai.engine import Engine
from colossalai.trainer import Trainer
from colossalai.core import global_context as gpc
model, train_dataloader, test_dataloader, criterion, optimizer, schedule, lr_scheduler = colossalai.initialize()
engine = Engine(
model=model,
criterion=criterion,
optimizer=optimizer,
lr_scheduler=lr_scheduler,
schedule=schedule
)
trainer = Trainer(engine=engine,
hooks_cfg=gpc.config.hooks,
verbose=True)
trainer.fit(
train_dataloader=train_dataloader,
test_dataloader=test_dataloader,
max_epochs=gpc.config.num_epochs,
display_progress=True,
test_interval=5
)
Write a Simple 2D Parallel Model
Let's say we have a huge MLP model and its very large hidden size makes it difficult to fit into a single GPU. We can then distribute the model weights across GPUs in a 2D mesh while you still write your model in a familiar way.
from colossalai.nn import Linear2D
import torch.nn as nn
class MLP_2D(nn.Module):
def __init__(self):
super().__init__()
self.linear_1 = Linear2D(in_features=1024, out_features=16384)
self.linear_2 = Linear2D(in_features=16384, out_features=1024)
def forward(self, x):
x = self.linear_1(x)
x = self.linear_2(x)
return x
Features
Colossal-AI provides a collection of parallel training components for you. We aim to support you to write your distributed deep learning models just like how you write your single-GPU model. We provide friendly tools to kickstart distributed training in a few lines.
- Data Parallelism
- Pipeline Parallelism
- 1D, 2D, 2.5D, 3D and sequence parallelism
- Friendly trainer and engine
- Extensible for new parallelism
- Mixed Precision Training
- Zero Redundancy Optimizer (ZeRO)
Cite Us
@article{bian2021colossal,
title={Colossal-AI: A Unified Deep Learning System For Large-Scale Parallel Training},
author={Bian, Zhengda and Liu, Hongxin and Wang, Boxiang and Huang, Haichen and Li, Yongbin and Wang, Chuanrui and Cui, Fan and You, Yang},
journal={arXiv preprint arXiv:2110.14883},
year={2021}
}