2015-11-18 15:25:20 7524 [Note] InnoDB: Highest supported file format is Barracuda.
2015-11-18 15:25:21 7524 [Note] InnoDB: 128 rollback segment(s) are active.
2015-11-18 15:25:21 7524 [Note] InnoDB: Waiting for purge to start
2015-11-18 15:25:21 7524 [Note] InnoDB: Percona XtraDB (http://www.percona.com) 5.6.27-75.0 started; log sequence number 288249230
2015-11-18 15:25:21 7524 [Note] Server hostname (bind-address): '*'; port: 3306
2015-11-18 15:25:21 7524 [Note] IPv6 is available.
2015-11-18 15:25:21 7524 [Note] - '::' resolves to '::';
2015-11-18 15:25:21 7524 [Note] Server socket created on IP: '::'.
2015-11-18 15:25:21 7524 [Note] Event Scheduler: Loaded 0 events
2015-11-18 15:25:21 7524 [Note] /home/openxs/dbs/p5.6/bin/mysqld: ready for connections.
Version: '5.6.27-75.0' socket: '/tmp/mysql.sock' port: 3306 MySQL Community Server (GPL)
So, the same stage of startup on the same hardware takes 6 seconds with P_S and table_definition_cache of 20000, 23 seconds with 50000 and one second with 50000 when performance_schema is disabled.
This can be observed, to some extent, with just about 30000 tables on 5.6.27:
bin/mysqld_safe --no-defaults --table_ definition_ cache=20000 &
2015-11-18 15:22:00 7271 [Note] InnoDB: Highest supported file format is Barracuda.
2015-11-18 15:22:06 7271 [Note] InnoDB: 128 rollback segment(s) are active.
bin/mysqld_safe --no-defaults --table_ definition_ cache=50000 &
2015-11-18 15:22:40 7382 [Note] InnoDB: Highest supported file format is Barracuda.
2015-11-18 15:23:03 7382 [Note] InnoDB: 128 rollback segment(s) are active.
bin/mysqld_safe --no-defaults --table_ definition_ cache=50000 --performance_ schema= OFF &
2015-11-18 15:25:20 7524 [Note] InnoDB: Highest supported file format is Barracuda. www.percona. com) 5.6.27-75.0 started; log sequence number 288249230 dbs/p5. 6/bin/mysqld: ready for connections.
2015-11-18 15:25:21 7524 [Note] InnoDB: 128 rollback segment(s) are active.
2015-11-18 15:25:21 7524 [Note] InnoDB: Waiting for purge to start
2015-11-18 15:25:21 7524 [Note] InnoDB: Percona XtraDB (http://
2015-11-18 15:25:21 7524 [Note] Server hostname (bind-address): '*'; port: 3306
2015-11-18 15:25:21 7524 [Note] IPv6 is available.
2015-11-18 15:25:21 7524 [Note] - '::' resolves to '::';
2015-11-18 15:25:21 7524 [Note] Server socket created on IP: '::'.
2015-11-18 15:25:21 7524 [Note] Event Scheduler: Loaded 0 events
2015-11-18 15:25:21 7524 [Note] /home/openxs/
Version: '5.6.27-75.0' socket: '/tmp/mysql.sock' port: 3306 MySQL Community Server (GPL)
So, the same stage of startup on the same hardware takes 6 seconds with P_S and table_definitio n_cache of 20000, 23 seconds with 50000 and one second with 50000 when performance_schema is disabled.