ROS2: memory leak

[keukenrol]

Hi

when implementing the neopixel library in a ROS2 node, I get the following error:

Failed to create mailbox device
: Operation not permitted
Traceback (most recent call last):
  File "/home/ubuntu/turtlebot3_ws/src/install/test_nodes/lib/test_nodes/ledSub", line 11, in <module>
    load_entry_point('test-nodes==0.0.0', 'console_scripts', 'ledSub')()
  File "/home/ubuntu/turtlebot3_ws/src/install/test_nodes/lib/python3.8/site-packages/test_nodes/ledSub.py", line 82, in main
    pixel_node = pixelNode()
  File "/home/ubuntu/turtlebot3_ws/src/install/test_nodes/lib/python3.8/site-packages/test_nodes/ledSub.py", line 44, in __init__
    self.pixels.show()
  File "/usr/local/lib/python3.8/dist-packages/adafruit_pixelbuf.py", line 205, in show
    return self._transmit(self._post_brightness_buffer)
  File "/usr/local/lib/python3.8/dist-packages/neopixel.py", line 180, in _transmit
    neopixel_write(self.pin, buffer)
  File "/usr/local/lib/python3.8/dist-packages/neopixel_write.py", line 38, in neopixel_write
    return _neopixel.neopixel_write(gpio, buf)
  File "/usr/local/lib/python3.8/dist-packages/adafruit_blinka/microcontroller/bcm283x/neopixel.py", line 82, in neopixel_write
    raise RuntimeError(
RuntimeError: ws2811_init failed with code -9 (Failed to create mailbox device)
swig/python detected a memory leak of type 'ws2811_t *', no destructor found.

This is my node:

class pixelNode(Node):

    def __init__(self, pixel_pin = board.D18, num_pixels = 34, ORDER = neopixel.GRB):       
        super().__init__('pixel_node')

        self.subscription = self.create_subscription(
            String,
            'bot_state',
            self.listener_callback,
            10)
        self.subscription  # prevent unused variable warning
        self.pixels = neopixel.NeoPixel(pixel_pin, num_pixels, brightness=0.5, auto_write=False, pixel_order=ORDER)
        self.pixels.fill((255, 0, 0))
        self.pixels.show()

        # blue led blinker
        timer_period = 0.5  # 2Hz
        self.timer = self.create_timer(timer_period, self.timer_callback)

    def listener_callback(self, msg):        
        if msg.data == 'driving':
            self.pixels.fill((255, 255, 255))
            self.get_logger().info('LEDS: DRIVING')

        elif msg.data == 'detected':
            self.pixels.fill((255, 127, 0))
            self.get_logger().info('LEDS: DETECTED')

        elif msg.data == 'shoot':
            self.pixels.fill((255, 0, 255))
            self.get_logger().info('LEDS: SHOOT')

        else:
            self.pixels.fill((255, 0, 0))
            self.get_logger().info('LEDS: UNKNOWN')

        self.pixels.show()

    def timer_callback(self):
        global bluestate

        if bluestate == 0:
            GPIO.output(25, GPIO.HIGH)
            bluestate = 1
        else:
            GPIO.output(25, GPIO.LOW)
            bluestate = 0

This is triggered when calling the function self.pixels.show(), which is inside a subscriber callback of a node. Any idea how to solve?

ROS2 Foxy Ubuntu 20.04 Raspberry Pi 4 Similar issues: https://github.com/jgarff/rpi_ws281x/issues/263 If I use the neopixel functions in a generic python script no issue arises. Thus the combination of ROS2 with neopixel is the issue Thanks!

[ealaimo18]

Did you ever solve this? Running into the same issue now running that library on Ros2.

[keukenrol]

Did you ever solve this? Running into the same issue now running that library on Ros2.

No, we ended up running the script separately.