gevent python3.7 + ThreadPoolExecutor block main thread

[ClericPy]

• gevent version: 1.3.4
• Python version: 3.7.0 (v3.7.0:1bf9cc5093, Jun 27 2018, 04:06:47) [MSC v.1914 32 bit (Intel)] downloaded from python.org
• Operating System: Windows-10-10.0.16299-SP0

Description:

gevent + python3.7 + ThreadPoolExecutor will block main thread forever while running future.result(). seems like something about _thread.allocate_lock.acquire.

only python3.7 hit that issue

python3.6+ubuntu18.04 + gevent 1.3.4 runs ok

python3.7+ubuntu18.04 + gevent 1.3.4 runs bad

What I've run:

from gevent import monkey

monkey.patch_all()

from concurrent.futures import ThreadPoolExecutor
import requests

pool = ThreadPoolExecutor()

task = pool.submit(requests.get, "http://python.org")
task.add_done_callback(lambda r: print(r.result(), 'done'))
print(task.result())

output:

and then blocking...............

[wwqgtxx]

please try #1248

[ClericPy]

@wwqgtxx thanks very much, close this issue for duplicate.

[jamadden]

Sure enough, on 3.7, ThreadPoolExecuter was changed to use queue.SimpleQueue; on 3.6 it uses queue.Queue.

[ClericPy]

@jamadden thank you for answering, will gevent do that trick in the future versions?

[jamadden]

@ClericPy See #1253. I was on the fence about having gevent do that patch (it's never patched queue before) but this example convinced me that it was the right thing.

[ClericPy]

waiting for the wonderful lib's updating ^-^