[Bug] Sudden high latency between publisher and subscriber

[aipiano]

Describe the bug

I use zenoh python to pub and sub a small message(about 512 bytes) and measure the delay between pub and sub.
It may delay about 5 seconds when I run the script for a long enough time.

Is it a bug?
Or how can I tune the performance by config.

To reproduce

Publisher:

session = zenoh.open(zenoh.Config())
pub = session.declare_publisher("some/key")

while True:
    rb = random.randbytes(512)
    timestamp = int(time.time() * 1000)
    print(timestamp)
    pub.put(rb, attachment=f"{timestamp}")
    time.sleep(0.05)

Subscriber:

session = zenoh.open(zenoh.Config())
sub = session.declare_subscriber("some/key")

for sample in sub:
    timestamp = int(time.time() * 1000)
    b = sample.payload.to_bytes()
    t = sample.attachment.to_string()
    print(f"Delay time {int(timestamp) - int(t)}")

System info

Platform: Ubuntu22.04 64bits
Zenoh version: 1.4.0
CPU: Intel Core i7-13700H