MySQL Bugs: #77491: we need separate 'global' configuration for replication.

Bug #77491	we need separate 'global' configuration for replication.
Submitted:	25 Jun 2015 21:12	Modified:	26 Jun 2015 17:06
Reporter:	Domas Mituzas	Email Updates:
Status:	Verified	Impact on me:	None
Category:	MySQL Server: Replication	Severity:	S4 (Feature request)
Version:	5.6+	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
currently there're two ways to set session parameters - globally and per-session.
unfortunately, there's no way to do that for replication threads, so they end up inheriting global settings and don't have client settings passed over in any form.

given a parameter like "max tmp table size" (exists in non-MySQL builds), one may want to have separate settings on master and slave. I could probably come up with list of parameters that we'd want to set differently in replication for standard mysql builds too.

As query execution in MySQL replication is not deterministic, it may make sense to support different settings on masters and slaves. 

How to repeat:
START SLAVE;

Suggested fix:
Implement SET @@replication.blah=... ; facility for session variables.

Domas,

You will not believe me, but  there are already some discussion on this subject. Your request is only an extension of the ideas we were discussing. Hence, we shall truly take it under advisement.

Verified as a valid feature request for the Replication.