Method AllowsSyncOnCompletion

tensorflow/core/common_runtime/device.h:127–127

On session completion, the executor may call Device::Sync() depending on flag settings. Override this to return false for devices that don't allow such calls. Instead, these devices must use other mechanisms (such as num_deferred_ops) to ensure the device has finished processing necessary work at session completion. In addition, for these devices, RefreshStatus must be called at session completion

  //
  // Devices that override this function must also implement RefreshStatus.
  virtual bool AllowsSyncOnCompletion() const { return true; }

  // This is used in conjunction with AllowsSyncOnCompletion to allow the
  // executor to get execution result status at session completion.