Setting Up the InnoDB memcached Plugin HYDERABAD|TELANGANA|IN END Traditional  memcached  configuration options may be specified in a MySQL configuration file or a  mysqld startup string, encoded in the argument of the  daemon_memcached_option  configuration parameter. memcached  configuration options take effect when the plugin is loaded, which occurs each time the MySQL server is started. For example, to make  memcached  listen on port 11222 instead of the default port 11211, specify  -p11222 as an argument of the  daemon_memcached_option  configuration option: mysqld .... --daemon_memcached_option="-p11222" Other  memcached  options can be encoded in the  daemon_memcached_option  string. For example, you can specify options to reduce the maximum number of simultaneous connections, change the maximum memory size for a key-value pair, or enable debugging messages for the error log, and so on. There are also configuration options specific to the  daemon_memcached  plugin. These include: By default, you do not need to modify  daemon_memcached_engine_lib_name  or daemon_memcached_engine_lib_path . You might configure these options if, for example, you want to use a different storage engine for  memcached  (such as the NDB  memcached  engine). daemon_memcached  plugin configuration parameters may be specified in the MySQL configuration file or in a  mysqld  startup string. They take effect when you load the  daemon_memcached  plugin. When making changes to  daemon_memcached  plugin configuration, reload the plugin to apply the changes. To do so, issue the following statements: mysql>  UNINSTALL PLUGIN daemon_memcached; mysql>  INSTALL PLUGIN daemon_memcached soname "libmemcached.so"; Configuration settings, required tables, and data are preserved when the plugin is restarted. For additional information about enabling and disabling plugins, see Section 5.6.1, “Installing and Uninstalling Plugins” . 3362 Configuring the InnoDB memcached Plugin • daemon_memcached_engine_lib_name : Specifies the shared library that implements the  InnoDB memcached  plugin. The default setting is  innodb_engine.so . • daemon_memcached_engine_lib_path : The path of the directory containing the shared library that implements the  InnoDB memcached  plugin. The default is NULL, representing the plugin directory. • daemon_memcached_r_batch_size : Defines the batch commit size for read operations ( get ). It specifies the number of  memcached  read operations after which a commit occurs. daemon_memcached_r_batch_size  is set to 1 by default so that every  get  request accesses the most recently committed data in the  InnoDB  table, whether the data was updated through  memcached or by SQL. When the value is greater than 1, the counter for read operations is incremented with each get  call. A  flush_all  call resets both read and write counters. • daemon_memcached_w_batch_size : Defines the batch commit size for write operations ( set , replace ,  append ,  prepend ,  incr ,  decr , and so on).  daemon_memcached_w_batch_size  is set to 1 by default so that no uncommitted data is lost in case of an outage, and so that SQL queries on the underlying table access the most recent data. When the value is greater than 1, the counter for write operations is incremented for each  add ,  set ,  incr ,  decr , and  delete  call. A  flush_all  call resets both read and write counters.