code: def test_memory_tracking_fsdp(self) -> None:
      with with_temp_files(count=1) as sync_file:
          world_size = 2
          mp.spawn(
              self._layer_memory_tracking_worker,
              (sync_file, world_size),
              nprocs=world_size,
          )
  
file_path: vissl/tests/test_layer_memory_tracking.py
imports: import unittest
  import torch
  import torch.distributed
  import torch.multiprocessing
  import torch.nn
  import torchvision.models
  from fairscale.nn import FullyShardedDataParallel
  from vissl.utils.layer_memory_tracking import find_best_reset_points, LayerwiseMemoryTracker, ProcessGroupTracker
  from vissl.utils.test_utils import gpu_test, init_distributed_on_file, with_temp_files, with_timing
label_desc: Use image node_id 3 for calling the TestLayerMemoryTracking obj's underlying member method code with example usage: obj.test_memory_tracking_fsdp() without return types