'localhost failed chunk' is a Joomla message, not a PHP or MySQL message, and you'll have to ask Joomla exactly what it means.
PHP parameters can be changed by : Left-click -> PHP -> PHP Configuration
MySQL parameters can be changed by : Left-click -> MySQL -> MySQL configuration
Some PhpMyAdmin parameters can be changed by :
Left-click -> PhpMyAdmin -> php_admin_value - php_admin_flag
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Documentation Apache -
Documentation PHP -
Documentation MySQL -
Wampserver install files & addons