The array should be named $t3p_scalable_conf . Its very important to disable persistent connections to MySQL.

Database configuration

In this example you have a MySQL architecture ('db' section) with 1 master host that will be the target of your data modification queries. This Master host its the default TYPO3 database host (array('host'=>$typo_db_host , 'port'=>3306, 'user'=>$typo_db_username, 'pass'=>''))

you could add more hosts if you have a multimaster MySQL.

Also you have 2 slaves (replications slaves) MySQL hosts: the default TYPO3 host and other '192.168.1.56' . This second server could be elected 3 times more than the first one. The slaves servers will be the targets of SELECT queries

VERY IMORTANT: databasename have to be same in all database servers.

Memcached configuration

The configuration of server works in the same way as in database servers.

I you set 'defaultTryMemcached' => TRUE then all of your SELECT queries will try to use memcached at less you add a flag to your exec_SELECTquery to avoid it.

Now the exec_SELECTquery have this signature: exec_SELECTquery($select_fields,$from_table,$where_clause,$groupBy='',$orderBy='',$limit='',$tryMemcached='') to give more control to developers.

If you set $tryMemcached=FALSE then query wont be stored in memcached.

If you set $tryMemcached=TRUE then query will be stored in memcached.

If you dont set $tryMemcached the deault action 'defaultTryMemcached' => TRUE its considered