[Bug] MavFTP checksum computes synchronously

[Martoon-00]

Describe the bug

From what I can tell, handler for CRC32 computation of MavFTP happens in the same thread as Mavlink handler. This can effectively clog Mavlink messages processing?

In practice I see that attempt to send CalcFileCRC32 request for a flight log file of 35Mb size results in no other message being processed over 20+ seconds.

Flight Log / Additional Information

I cannot attach any logs or information unfortunately, can only tell that I'm using a fork of PX4 based on 1.16.0 and witnessed the issue there. But I'm willing to close this ticket if my suggestion about the code is wrong.

[dakejahl]

Sounds about right. The microservices running under the mavlink_receiver thread is a known architectural problem. Fixing it properly would require reworking the mavlink module, e.g. with Tx/Rx queues and time slicing services and message streams.