NCCL报错
1、报错信息：
raise RuntimeError("Distributed package doesn't have NCCL " "built in")
RuntimeError: Distributed package doesn't have NCCL built in
2、报错原因：
windows系统不支持nccl，采用gloo；
3、报错解决：
代码开头添加：
import os
os.environ["PL_TORCH_DISTRIBUTED_BACKEND"] = "gloo"或者
init_process_group(backend="nccl", rank=rank, world_size=world_size)
# 修改为
init_process_group(backend="gloo", rank=rank, world_size=world_size)# windows users may have to use "gloo" instead of "nccl" as backend
# nccl: NVIDIA Collective Communication Library#
#windows用户可能必须使用“gloo”而不是“nccl”作为后端
#nccl：NVIDIA集体通信库