Use torch.cuda.device_count() (#126)

deepspeed/pt/deepspeed_run.py

@@ -5,7 +5,6 @@ Copyright 2020 The Microsoft DeepSpeed Team
 import os
 import sys
 import json
-import pynvml
 import shutil
 import base64
 import logging
@@ -13,6 +12,9 @@ import argparse
 import subprocess
 import collections
 from copy import deepcopy
+
+import torch.cuda
+
 from deepspeed.pt.deepspeed_constants import TORCH_DISTRIBUTED_DEFAULT_PORT
 
 DLTS_HOSTFILE = "/job/hostfile"
@@ -213,19 +215,6 @@ def parse_inclusion_exclusion(resource_pool, inclusion, exclusion):
                                  exclude_str=exclusion)
 
 
-def local_gpu_count():
-    device_count = None
-    try:
-        pynvml.nvmlInit()
-        device_count = pynvml.nvmlDeviceGetCount()
-        print("device count", device_count)
-        return device_count
-    except pynvml.NVMLError:
-        logging.error("Unable to get GPU count information, perhaps there are "
-                      "no GPUs on this host?")
-        return device_count
-
-
 def encode_world_info(world_info):
     world_info_json = json.dumps(world_info).encode('utf-8')
     world_info_base64 = base64.urlsafe_b64encode(world_info_json).decode('utf-8')
@@ -243,8 +232,8 @@ def main(args=None):
     resource_pool = fetch_hostfile(args.hostfile)
     if not resource_pool:
         resource_pool = {}
-        device_count = local_gpu_count()
-        if device_count is None:
+        device_count = torch.cuda.device_count()
+        if device_count == 0:
             raise RuntimeError("Unable to proceed, no GPU resources available")
         resource_pool['localhost'] = device_count
         args.master_addr = "127.0.0.1"

requirements.txt

@@ -5,7 +5,6 @@ tqdm
 psutil
 tensorboardX==1.8
 tensorflow-gpu==1.15.2
-nvidia-ml-py3
 pytest
 pytest-forked
 pre-commit