Limited INFO logging during rebalance

[erikvanoosten]

We have some very nice logging statements that could give insight when a rebalance goes wrong. However, because of the frequency and size of the logging, we currently log it at the DEBUG level. (See #1375 (comment).)

We would like to log this information at the INFO level, but not too often. For example, only after 3 seconds since the start of the rebalance, and then once every 3 seconds.

[lemony312]

The code has changed slighlty since this issue was opened - is this still a valid issue to address?

[erikvanoosten]

The code has changed slighlty since this issue was opened - is this still a valid issue to address?

Thanks for checking. Yes, IMHO this is still relevant. In particular for this logging statement:

zio-kafka/zio-kafka/src/main/scala/zio/kafka/consumer/internal/RebalanceCoordinator.scala

Lines 97 to 100 in da10682

	ZIO.logDebug(
	s"Delaying rebalance until ${streamsToEnd.size} streams (of revoked partitions) have committed " +
	s"the offsets of the records they consumed. Deadline in ${timeToDeadlineMillis()}ms. $statusStrings"
	)