kazoo client hangs with multiprocess

[fopguy41]

kazoo client hangs when I use it within multiprocess.

I'm thinking it's most likely because it's not safe for a child and parent process to share kazoo client.

If that's true, what is the safe way for share a kazoo client within the same process, but still prevent hanging when using multiprocess?

Snippet to Reproduce the Problem

The following code is fine when using single process

client = None
def get_shared_kazoo_client():
    """ returns shared kazoo client"""
    from kazoo.client import KazooClient
    global client
    if client is None:
        client = KazooClient(hosts=KAZOOCLIENT)
        client.start()
    return client

def semaphore_function():
    client = get_shared_kazoo_client()
    throttler = client.Semaphore(max_leases=4, path='/test/path')
    with throttler:
        logging.info("inside")

if __name__ == '__main__':
    semaphore_function()
    semaphore_function()

This is fine no matter how many times I call semaphore_function().

However, the following code would hang.

if __name__ == '__main__':
    semaphore_function()
    p = mp.Process(target=semaphore_function)
    p.start()
    p.join()

The child process starts, but is unable to ever past with throttler.

I believe this post is observing similar behavior. https://github.com/python-zk/kazoo/issues/519

I would like to have a global shared kazoo client to prevent unnecessarily constructing new kazoo clients over and over again. But, it fails the moment I start multiprocessing.

Any comments would be much appreciated.

Specifications

• Kazoo version: 2.6.1
• Python version: 3.6
• OS: centOS 7

[wlazjr]

any progress?