Comment 3 for bug 1257069

The point is that the DDL is in another database altogether.

We (and many other) application developers partition (not shard) our applications for scalability using the Database as a strongly walled partition. We never run DDL, transactions or updates that span multiple Databases.

As servers grow more and more powerful, the circumstance where a database may share a server with another database will grow. We have >400 databases per server with current commodity hardware and expect this to grow

Perhaps you should allow an option that we could enable that would limit this serialisation to within a single database. e.g.

wsrep_ddl_lock=server|database

We could then tune the setting to match our application.

Regards
Jeff