mysqlnd-mux-php-sharing_connections-7

  • Concepts
  • Sharing connections

  • Sharing connections
  • Sharing connections

    Sharing connections

    The PHP mysqlnd connection multiplexing plugin
    changes the relationship between a users connection handle and the
    underlying MySQL connection. Without the plugin, every MySQL
    connection belongs to exactly one user connection at a time. The
    multiplexing plugin changes. A MySQL connection is shared among
    multiple user handles. There no one-to-one relation if using the
    plugin.

    Sharing pooled connections has an impact on the
    connection state. State changing operations from multiple user
    handles pointing to one MySQL connection are not isolated from each
    other. If, for example, a session variable is set through one user
    connection handle, the session variable becomes visible to all
    other user handles that reference the same underlying MySQL
    connection.

    This is similar in concept to connection state
    related phenomens described for the PHP mysqlnd replication and
    load balancing plugin. Please, check the PECL/mysqlnd_ms
    documentation
    for more details on the state of a
    connection.

    The proof-of-concept takes no measures to isolate
    multiplexed connections from each other.