ProxySQL is a fast, reliable MySQL proxy with advanced runtime configuration management (virtually no configuration change requires a restart).
.
It features query routing, query caching, query rewriting (for queries generated by ORMs, for example) and is most of the time a drop-in replacement for mysqld from the point of view of the application. It can be configured and remote controlled through an SQL-compatible admin interface.
File: postinst
#!/bin/sh -e
mkdir -p /var/run/proxysql
if [ ! -d /var/run/proxysql ]; then mkdir /var/run/proxysql ; fi