Logging "Backends flushed" while dropping logs is counterproductive.

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Einar Thorsrud — Fri, 29 Apr 2022 13:10:03 GMT

Yes, that is unfortunately the case. I have bumped the issue but I cannot promise that it will be fixed (particularly as the nRF5 SDK is in maintenance mode).

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Anthony Ambuehl — Thu, 28 Apr 2022 22:45:35 GMT

BTW this problem still exists in SDK 17.0.2

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Eliot Stock — Fri, 26 Apr 2019 08:35:02 GMT

This is still there in SDK 15.3.0 and I'm hitting the same issue. Are you going to fix it?

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Einar Thorsrud — Fri, 12 Oct 2018 07:58:30 GMT

Hi,

You are right, of course (I was too quick when I looked at this initially.) I will report this internally.

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Anthony Ambuehl — Wed, 10 Oct 2018 16:38:36 GMT

Once again... the backend flush does not drop all logs. It only drops 1 log which gets replaced immediately with "Backends flushed" I know this from direct experience.

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Anthony Ambuehl — Fri, 05 Oct 2018 15:20:33 GMT

Backend flush drops a single log message. This is not the same as NRF_LOG_FLUSH(). Dropping a single log message and then generating a new log message is counterproductive.

For my code base I added an atomic counter for backend_flush() calls and report the number of flushes when the log buffer reaches empty.

RE: Logging "Backends flushed" while dropping logs is counterproductive.

Einar Thorsrud — Fri, 05 Oct 2018 11:46:52 GMT

Hi,

Thank you for your feedback. Personally, I think the current SDK implementation makes a lot of sense as it it can be very useful to see clearly where in the history logs were flushed. A flag does not do quite the same, as it will not show you where there are missing logs. In any case it is written after the logs were flushed there should still be plenty of room for other logs after writing this short string (if not you could either shorten the string even more or use a larger buffer if you have available memory).