• MySQL Native Driver Plugin
  • A comparison of mysqlnd plugins with MySQL

  • A comparison of mysqlnd plugins with MySQL Proxy
  • A comparison of mysqlnd plugins with MySQL

    A comparison of mysqlnd plugins with MySQL

    Mysqlnd plugins and MySQL Proxy are
    different technologies using different approaches. Both are valid
    tools for solving a variety of common tasks such as load balancing,
    monitoring, and performance enhancements. An important difference
    is that MySQL Proxy works with all MySQL clients, whereas
    mysqlnd plugins are specific to PHP applications.

    As a PHP Extension, a mysqlnd plugin gets
    installed on the PHP application server, along with the rest of
    PHP. MySQL Proxy can either be run on the PHP application server or
    can be installed on a dedicated machine to handle multiple PHP
    application servers.

    Deploying MySQL Proxy on the application server has
    two advantages:

    1. No single point of failure

    2. Easy to scale out (horizontal scale out, scale by

    MySQL Proxy (and mysqlnd plugins) can
    solve problems easily which otherwise would have required changes
    to existing applications.

    However, MySQL Proxy does have some

    • MySQL Proxy is a new component and technology to
      master and deploy.

    • MySQL Proxy requires knowledge of the Lua scripting

    MySQL Proxy can be customized with C and Lua
    programming. Lua is the preferred scripting language of MySQL
    Proxy. For most PHP experts Lua is a new language to learn. A
    mysqlnd plugin can be written in C. It is also possible to
    write plugins in PHP using » PECL/mysqlnd_uh.

    MySQL Proxy runs as a daemon – a background
    process. MySQL Proxy can recall earlier decisions, as all state can
    be retained. However, a mysqlnd plugin is bound to the
    request-based lifecycle of PHP. MySQL Proxy can also share one-time
    computed results among multiple application servers. A
    mysqlnd plugin would need to store data in a persistent
    medium to be able to do this. Another daemon would need to be used
    for this purpose, such as Memcache. This gives MySQL Proxy an
    advantage in this case.

    MySQL Proxy works on top of the wire protocol. With
    MySQL Proxy you have to parse and reverse engineer the MySQL Client
    Server Protocol. Actions are limited to those that can be achieved
    by manipulating the communication protocol. If the wire protocol
    changes (which happens very rarely) MySQL Proxy scripts would need
    to be changed as well.

    Mysqlnd plugins work on top of the C API,
    which mirrors the libmysqlclient client and Connector/C
    APIs. This C API is basically a wrapper around the MySQL Client
    Server protocol, or wire protocol, as it is sometimes called. You
    can intercept all C API calls. PHP makes use of the C API,
    therefore you can hook all PHP calls, without the need to program
    at the level of the wire protocol.

    Mysqlnd implements the wire protocol.
    Plugins can therefore parse, reverse engineer, manipulate and even
    replace the communication protocol. However, this is usually not

    As plugins allow you to create implementations that
    use two levels (C API and wire protocol), they have greater
    flexibility than MySQL Proxy. If a mysqlnd plugin is
    implemented using the C API, any subsequent changes to the wire
    protocol do not require changes to the plugin itself.