[Discuss] "This plugin slows down Homebridge..."
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**Describe Your Problem:**
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As a developer, I'd like to know what's the typical timeout from Homebridge to show the slow logs. In the wiki, it's suggested to call [`callback()` immediately](https://github.com/homebridge/homebridge/wiki/Characteristic-Warnings).

As a Node.js developer, I would expect callback/promise methods to allow async behaviours. If a method is expected to be sync, it'd rather return instead.

In my plugin, I'm asking the accessory about their state over the local connection. Some users are complaining that they're seeing those log entries (typically because they're experiencing some Network issues themselves).

IMO, according to Node.js IO behaviours, slow network requests should not block anything on the bridge's behaviour to recommend the approach of calling `callback()` immediately and later use `characteristic.updateValue`. I think that this suggested approach also affects the UX because any action will always succeed, even when a network misconfiguration might cause timeouts. I'd rather let the user know by having the Home app (or Siri), claiming that it failed, rather than silent errors (only to be discovered when looking at the logs).

What do you think?
Also, what's the current timeout to show the slow-log?

[**Logs:**]()
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```
[5/16/2021, 4:19:22 AM] [homebridge-xiaomi-roborock-vacuum] This plugin slows down Homebridge. The read handler for the characteristic 'Serial Number' was slow to respond! See git.io/JtMGR for more info.
[5/16/2021, 7:01:53 AM] [homebridge-xiaomi-roborock-vacuum] This plugin slows down Homebridge. The read handler for the characteristic 'Firmware Revision' was slow to respond! See git.io/JtMGR for more info.
[5/16/2021, 9:45:03 AM] [homebridge-xiaomi-roborock-vacuum] This plugin slows down Homebridge. The read handler for the characteristic 'Serial Number' was slow to respond! See git.io/JtMGR for more info.
```

**Homebridge Config:**
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not relevant

**Screenshots:**
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**Environment:**

* **Node.js Version**: <!-- node -v -->
* **NPM Version**: <!-- npm -v -->
* **Homebridge Version**: <!-- homebridge -V -->
* **Operating System**: Raspbian / Ubuntu / Debian / Windows / macOS / Docker / other
* **Process Supervisor**: Systemd / init.d / pm2 / launchctl / Docker / hb-service / other / none

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