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qasync memory leak

See original GitHub issue

I have an example with pyzmq that is leaking around ~60mb/sec of memory. When I run pyzmq with the standard asyncio event loop everything seems to work fine, but using a QEventLoop I see this problem.

import os
import asyncio
import time
import zmq
import zmq.asyncio
import numpy as np
from multiprocessing import Process
from collections import namedtuple
from PyQt5 import QtWidgets
from qasync import QEventLoop

Addr = namedtuple('Addrs', ['name', 'view'])
addr = Addr('graph', 'tcp://')

def run_worker():
    ctx = zmq.Context()
    socket = ctx.socket(zmq.PUB)
    timestamp = 0

    while True:
            topic = 'view:graph:_auto_Projection.0.Out'
            socket.send_string(topic, zmq.SNDMORE)
            socket.send_pyobj(timestamp, zmq.SNDMORE)
            timestamp += 1
            msg = np.random.randn(1024, 1024)

        except KeyboardInterrupt:


async def update():
    ctx = zmq.asyncio.Context()
    sock = ctx.socket(zmq.SUB)
    sock.setsockopt_string(zmq.SUBSCRIBE, 'view:graph:_auto_Projection.0.Out')

    while True:
        topic = await sock.recv_string()
        heartbeat = await sock.recv_pyobj()
        reply = await sock.recv_pyobj()
        print("PID:", os.getpid(), "RECEIVED:", reply)

if __name__ == "__main__":
    worker = Process(target=run_worker)

    app = QtWidgets.QApplication([])
    loop = QEventLoop(app)
    task = asyncio.ensure_future(update())

        if not task.done():


Issue Analytics

  • State:open
  • Created 3 years ago
  • Reactions:1
  • Comments:5

github_iconTop GitHub Comments

syamajalacommented, Aug 20, 2020

The pyzmq developers responded and this bug does appear to be due to qasync/asyncqt

syamajalacommented, Aug 2, 2020

I swapped out zmq for tcp and its not leaking anymore, so i think this proves the leak is coming from pyzmq.

Read more comments on GitHub >

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