MySQL Bugs: #96126: Doxygen: InnoDB # of background log threads is incorrect

Bug #96126	Doxygen: InnoDB # of background log threads is incorrect
Submitted:	8 Jul 2019 15:01	Modified:	9 Jul 2019 13:40
Reporter:	Calvin Sun	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: Documentation	Severity:	S3 (Non-critical)
Version:	8.0.16	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
On InnoDB redo log doxygen page: https://dev.mysql.com/doc/dev/mysql-server/8.0.16/PAGE_INNODB_REDO_LOG_THREADS.html

Three background log threads are responsible for writes of new data to disk:
1.	Log writer - writes from the log buffer or write-ahead buffer to OS buffers.
2.	Log flusher - writes from OS buffers to disk (fsyncs).
3.	Log write_notifier - notifies user threads about completed writes to disk (when write_lsn is advanced).
4.	Log flush_notifier - notifies user threads about completed fsyncs (when flushed_to_disk_lsn is advanced).

Should be Four background log threads, not Three.

How to repeat:
Read the doc or code.

Suggested fix:
Correct the comment in log0write.cc:75: Three background log threads are responsible for writes of new data to disk:

HI Cheshung, my dear friend,

How are you ???

I agree with you 100 % and I am verifying this bug as a Documentation bug.

Verified as reported.