old_contents: # Copyright 2021 Google LLC
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     https://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  """Tests for cross host device transfer."""
  
  from absl.testing import absltest
  import unittest
  import numpy as np
  
  import jax
  from jax._src import test_util as jtu
  
  from jax.config import config
  
  config.parse_flags_with_absl()
  
  
  class RemoteTransferTest(jtu.JaxTestCase):
  
    def test_remote_transfer(self):
      if jax.device_count() < 2:
        raise unittest.SkipTest("Remote transfer requires at lest 2 devices")
      dev_a, dev_b = jax.local_devices()[:2]
      if not hasattr(dev_a.client, "make_cross_host_receive_buffers"):
        # TODO(jheek) remove this once a new version of JAX lib is released
        raise unittest.SkipTest("jax-lib doesn't include cross host APIs")
      send_buf = jax.device_put(np.ones((32,)), dev_a)
      shapes = [send_buf.xla_shape()]
      (tag, recv_buf), = dev_b.client.make_cross_host_receive_buffers(
          shapes, dev_b)
      status, dispatched = send_buf.copy_to_remote_device(tag)
      self.assertIsNone(status)
      self.assertTrue(dispatched)
      self.assertArraysEqual(send_buf, recv_buf)
  
  
  if __name__ == '__main__':
    absltest.main(testLoader=jtu.JaxTestLoader())
  
new_contents: # Copyright 2021 Google LLC
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     https://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  """Tests for cross host device transfer."""
  
  from absl.testing import absltest
  import unittest
  import numpy as np
  
  import jax
  from jax._src import test_util as jtu
  
  from jax.config import config
  
  config.parse_flags_with_absl()
  
  
  class RemoteTransferTest(jtu.JaxTestCase):
  
    # TODO(jheek): this test crashes on multi-GPU.
    @jtu.skip_on_devices("gpu")
    def test_remote_transfer(self):
      if jax.device_count() < 2:
        raise unittest.SkipTest("Remote transfer requires at lest 2 devices")
      dev_a, dev_b = jax.local_devices()[:2]
      if not hasattr(dev_a.client, "make_cross_host_receive_buffers"):
        # TODO(jheek) remove this once a new version of JAX lib is released
        raise unittest.SkipTest("jax-lib doesn't include cross host APIs")
      send_buf = jax.device_put(np.ones((32,)), dev_a)
      shapes = [send_buf.xla_shape()]
      (tag, recv_buf), = dev_b.client.make_cross_host_receive_buffers(
          shapes, dev_b)
      status, dispatched = send_buf.copy_to_remote_device(tag)
      self.assertIsNone(status)
      self.assertTrue(dispatched)
      self.assertArraysEqual(send_buf, recv_buf)
  
  
  if __name__ == '__main__':
    absltest.main(testLoader=jtu.JaxTestLoader())
  
subject: Disable remote_transfer_test on GPU. It currently crashes.