MySQL Thread Pool provides added scalability benefits in MySQL Enterprise Edition. (1)

Check

To see if the Thread Pool is active...

SELECT plugin_name, plugin_status

FROM information_schema.plugins

WHERE plugin_name LIKE '%thread%';

To check the Performance Schema monitoring tables are available...

SELECT table_name

FROM information_schema.tables

WHERE table_schema = 'performance_schema'

AND table_name LIKE 'tp%';

Enable

Add this to your /etc/my.cnf, in the [mysqld] stanza, and restart mysql...

plugin-load-add=thread_pool.so

Disable

Remove this line from your /etc/my.cnf and restart mysql...

plugin-load-add=thread_pool.so

Bibliography & References