Bug #57123 Wrong units documented for rpl_semi_sync_master_timeout
Submitted: 30 Sep 2010 8:13 Modified: 4 Oct 2010 15:55
Reporter: Andrew Morgan Email Updates:
Status: Closed Impact on me:
None 
Category:MySQL Server: Documentation Severity:S3 (Non-critical)
Version:5.5.6-rc OS:Any
Assigned to: Paul DuBois CPU Architecture:Any

[30 Sep 2010 8:13] Andrew Morgan
Description:
On http://dev.mysql.com/doc/refman/5.5/en/replication-semisync-installation.html it is stated:

"For rpl_semi_sync_master_timeout, the value N is given in seconds. The default value is 10."

Similarly at http://dev.mysql.com/doc/refman/5.5/en/server-system-variables.html#sysvar_rpl_semi_sync_m... :

"A value in seconds that controls how long the master waits on a commit for acknowledgment from a slave before timing out and reverting to asynchronous replication. The default value is 10 seconds."

When I check the real default value, this is what I get...

"
master> SHOW VARIABLES LIKE 'rpl_semi_sync_master_timeout';
+------------------------------+-------+
| Variable_name                | Value |
+------------------------------+-------+
| rpl_semi_sync_master_timeout | 10000 |
+------------------------------+-------+
"

Looks like the unit is really mille-seconds and the default is 10,000

How to repeat:
Compare the output from SHOW VARIABLES LIKE 'rpl_semi_sync_master_timeout'; with the documentation.

Suggested fix:
Either fix the documentation or if the documentation is correct then fix the code to use seconds.
[4 Oct 2010 15:55] Paul DuBois
Thank you for your bug report. This issue has been addressed in the documentation. The updated documentation will appear on our website shortly, and will be included in the next release of the relevant products.

You are correct. The unit is milliseconds and the default is 10000 (10 seconds).