Support to update configs without restarting BE #3268
Description
Is your feature request related to a problem? Please describe.
Now when we want to update some configs, like 'sleep_interval', 'compaction_threshold', we have to modify config values in be.conf and then restart BE process to reload the configs. Restart the process will stop all the working jobs on BE, for example stream load, scan, etc, we'd better provide a method to update configs without restarting the process.
Describe the solution you'd like
- Some configs in type of 'interval', 'threshold', 'enable flag' could be updated when BE is running
- Though HTTP API, and a simple staus will return to judge whether it is success ot not.
- For simplicity and safety, only a single config is able to update once by this API.
- To update mutiple configs, you can call this API several times.