code: public long getPreciseFreeMemory(int deviceId) {
          // we refresh free memory on device
          val extFree = NativeOpsHolder.getInstance().getDeviceNativeOps().getDeviceFreeMemory(deviceId);
          //freePerDevice.get(deviceId).set(extFree);
  
          return extFree;
      }
docs: This method returns precise amount of free memory on specified device
  @param deviceId
  @return