disable pin memory in ddp

Author: synml

cfgs/cityscapes.yaml

@@ -3,7 +3,7 @@ dataset:
   name: Cityscapes
   root: ../../data/cityscapes
   num_workers: 8
-  pin_memory: False
+  pin_memory: True
   normalize_mean: !!python/tuple [0.28689554, 0.32513303, 0.28389177]
   normalize_std: !!python/tuple [0.18696375, 0.19017339, 0.18720214]
 

utils/builder.py

@@ -60,6 +60,7 @@ def build_dataset(self, dataset_type: str, ddp_enabled=False) -> Tuple[torch.uti
         if ddp_enabled:
             sampler = torch.utils.data.DistributedSampler(dataset)
             shuffle = False
+            pin_memory = False
         else:
             sampler = None
         dataloader = torch.utils.data.DataLoader(dataset, batch_size=batch_size, shuffle=shuffle, sampler=sampler,