as in the title here, i updated php to 5.5.7 and enabled the opcache.
when i restarted the services for mysql, nginx and php-fpm i visited piwik and saw that the install process page was rendered and the message in a red error type box:
Your Piwik configuration file appears to be misconfigured. You can either remove config/config.ini.php and resume installation, or correct the database connection settings.
sqlstate[hy000]  the server requested authentication method unknown to the client
anyone know why this is ?
piwik v. 2.0.2