preload_libraries

Definition PG 8.1 manual

This variable specifies one or more shared libraries that are to be preloaded at server start. A parameterless initialization function can optionally be called for each library. To specify that, add a colon and the name of the initialization function after the library name. For example '$libdir/mylib:mylib_init' would cause mylib to be preloaded and mylib_init to be executed. If more than one library is to be loaded, separate their names with commas.

If a specified library or initialization function is not found, the server will fail to start.

PostgreSQL procedural language libraries may be preloaded in this way, typically by using the syntax '$libdir/plXXX:plXXX_init' where XXX is pgsql, perl, tcl, or python.

By preloading a shared library (and initializing it if applicable), the library startup time is avoided when the library is first used. However, the time to start each new server process may increase slightly, even if that process never uses the library. So this option is recommended only for libraries that will be used in most sessions.