We use spring-data-r2dbc:1.3.2 and dev.miku:r2dbc-mysql:0.8.2.RELEASE and experience a strange issue in production.

We don't understand what is the root cause and whether it is a recoverable or can really create unpredictable outcome (as the log suggests).

Periodically, we see error log as following:

• logger: dev.miku.r2dbc.mysql.client.ReactorNettyClient
• level: ERROR
• message: Exchange cancelled while exchange is active. This is likely a bug leading to unpredictable outcome.

We see it a few times a day and it makes us nervous since it explicitly states: This is likely a bug leading to unpredictable outcome

We do not get any additional info in the log.

A few questions:

1. Is it really dangerous or can we consider it as a warning?
2. How do we debug it in order to understand its cause?
3. From the source code we could see that it assumes that exchange request cannot be cancelled if it was not completed and consider this situation as a BUG. Does it make sense? What if reactive stream was cancelled due to 'connection drop' or any other reason?