[RFH] [DO NOT MERGE] aiohttp + wifi mesh networks results in request hangs

[Noltari]

Some users with Home Assistant behind Wifi Mesh networks are experiencing timeouts with the Airzone Cloud integration.
This integration uses aiohttp to communicate with the Cloud API and triggers most of the requests in parallel.

The issue is that some users, both of them with the Home Assistant server behind a Wifi mesh network are experiencing connection hangs which results in timeouts.
One of these users solved it by connecting the Home Assistant server to its router, but unfortunately this isn't possible for all of them.
However, it seems that limiting the number of parallel connections to 4 solves the issue.
It would be great if someone could shed some light here on how to fix this for these users.
Maybe there's something in aiohttp that I did wrong in my integration lib or something that can be tweaked...
I'm hoping that maybe someone has come across this issue in the past with a different integration...

(BTW, I'm opening this as a PR to have context about the integration and the debugging, but if this is not acceptable please tell me and I will create an issue or a post in the community)

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[elupus]

Just change to creating a new session and limit number of allowed parallel requests in the lib?

[Noltari]

Just change to creating a new session and limit number of allowed parallel requests in the lib?

Yes, but isn't it strange to do that just because some users are experiencing that kind of failure?
I mean, that's just a patch, but it shouldn't be needed if things were working correctly, right?
The thing is I want to fix the root cause, not workaround it :$

[elupus]

Ps. I meant async_create_clientsession.

But yes seems a bit strange, i didnt realize it was not a integration issue per say.

That said.. There is a point in avoiding massive number of parallel requests against cloud services anyway. They put a large burdon, with little gain.

Maybe we do want some per server limit in parallel requests. But setting a limit globally would be hard.

[Noltari]

Ps. I meant async_create_clientsession.

I don't think this would be fixed with async_create_clientsession because I've tried running the aioairzone-cloud examples in those environments and those fail too.
In fact in order to get them working I had to limit the number of connections to 4:
Noltari/aioairzone-cloud@d521736

It's strange that I can use the same account on my Home Assistant setup and I have no issues at all...

[Noltari]

After further testing I would say this is related to this aiohttp issue:
aio-libs/aiohttp#3698

Because I've tested creating a new ClientSession() for each API request and it fixes the issue...