Bug #108821 DOC issue with group_replication_communication_debug_options description
Submitted: 19 Oct 2022 10:01 Modified: 16 Nov 2022 13:46
Reporter: Przemyslaw Malkowski Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:8.0.31 OS:Any
Assigned to: CPU Architecture:Any
Tags: group replication

[19 Oct 2022 10:01] Przemyslaw Malkowski
Description:
In https://dev.mysql.com/doc/refman/8.0/en/group-replication-options.html#sysvar_group_replic... we can read:

"The value of this system variable can be changed while Group Replication is running, but the change only takes effect after you stop and restart Group Replication on the group member."

However, I can see the change takes effect immediately (as long as GCS_DEBUG_TRACE file is there).

How to repeat:
node1 > select @@version,@@group_replication_communication_debug_options;
+-----------+-------------------------------------------------+
| @@version | @@group_replication_communication_debug_options |
+-----------+-------------------------------------------------+
| 8.0.31    | GCS_DEBUG_NONE                                  |
+-----------+-------------------------------------------------+
1 row in set (0.00 sec)

$ tail -f data/GCS_DEBUG_TRACE
(empty)

node1 > set global group_replication_communication_debug_options=GCS_DEBUG_BASIC;
Query OK, 0 rows affected (0.00 sec)

$ tail -f data/GCS_DEBUG_TRACE
[MYSQL_GCS_DEBUG] [GCS] Sending message.
[MYSQL_GCS_DEBUG] [GCS] Sending message.
[MYSQL_GCS_DEBUG] [GCS] Sending message.
...

Suggested fix:
Correct the documentation.
[19 Oct 2022 10:48] MySQL Verification Team
Hello Przemyslaw,

Thank you for the report. 

Thanks,
Umesh
[16 Nov 2022 13:46] Margaret Fisher
Posted by developer:
 
Thanks for pointing this out! I have made the correction and it should show in the published docs soon.