TYPO3 Core

I made a setup which runs on two different hosts, with a MySQL master (A) and slave (B) replication. However, there is IMHO a lot of optimization potential.

The main problem occurs when visiting the page on B. As TYPO3 wants to write data to e.g fe_session_data or index_*, the slave will lock up on the next few transactions because of a duplicate primary key error. However, setting B's mysql to read only will result in failed queries.

Related: http://forge.typo3.org/issues/17088

I am not sure if that would generally help, but maybe an option in the install tool to set the TYPO3 instance to a "slave" mode would trigger a switch in the persistence layer to not execute INSERT and UPDATE statements on the slave. Of course, this would be extension- and setup-dependent, because you can't e.g. edit your fe_user profile on the slave then.

I just wanted to "braindump" this here, maybe it results in a constructive discussion and an enhancement to TYPO3, or it gets ignored or buried.