EasyCV/tools/launch.py

103 lines
3.3 KiB
Python

# Copyright (c) Alibaba, Inc. and its affiliates.
from __future__ import (absolute_import, division, print_function,
unicode_literals)
import os
import subprocess
import sys
from argparse import REMAINDER, ArgumentParser
def parse_args():
"""
Helper function parsing the command line options
@retval ArgumentParser
"""
parser = ArgumentParser(description='PyTorch distributed training launch '
'helper utilty that will spawn up '
'multiple distributed processes')
# Optional arguments for the launch helper
parser.add_argument(
'--nproc_per_node',
type=int,
default=1,
help='The number of processes to launch on each node, '
'for GPU training, this is recommended to be set '
'to the number of GPUs in your system so that '
'each process can be bound to a single GPU.')
parser.add_argument(
'--local_mode',
action='store_true',
help='If assigned, traning_script should be path of python'
'script, otherwise python module name')
# positional
parser.add_argument(
'training_script',
type=str,
help='The full path to the single GPU training '
'program/script to be launched in parallel, '
'followed by all the arguments for the '
'training script',
default='tools/train.py')
# rest from the training program
parser.add_argument('training_script_args', nargs=REMAINDER)
return parser.parse_args()
def main():
args = parse_args()
args.node_rank = int(os.environ.get('RANK', '0'))
args.nnodes = int(os.getenv('WORLD_SIZE', '1'))
# world size in terms of number of processes
dist_world_size = args.nproc_per_node * args.nnodes
# set PyTorch distributed related environmental variables
current_env = os.environ.copy()
current_env['WORLD_SIZE'] = str(dist_world_size)
processes = []
if 'OMP_NUM_THREADS' not in os.environ and args.nproc_per_node > 1:
current_env['OMP_NUM_THREADS'] = str(1)
print('*****************************************\n'
'Setting OMP_NUM_THREADS environment variable for each process '
'to be {} in default, to avoid your system being overloaded, '
'please further tune the variable for optimal performance in '
'your application as needed. \n'
'*****************************************'.format(
current_env['OMP_NUM_THREADS']))
for local_rank in range(0, args.nproc_per_node):
# each process's rank
dist_rank = args.nproc_per_node * args.node_rank + local_rank
current_env['RANK'] = str(dist_rank)
current_env['LOCAL_RANK'] = str(local_rank)
# spawn the processes
cmd = [sys.executable, '-u']
if not args.local_mode:
cmd.append('-m')
cmd.append(args.training_script)
cmd.append('--local_rank={}'.format(local_rank))
cmd.extend(args.training_script_args)
process = subprocess.Popen(cmd, env=current_env)
processes.append(process)
for process in processes:
process.wait()
if process.returncode != 0:
raise subprocess.CalledProcessError(
returncode=process.returncode, cmd=cmd)
if __name__ == '__main__':
main()