gistfile1.php

<?php

/*
 new flag for xhprof_enable (third parameter) if set to false, instead of ignoring the passed array of
 function names, it will profile only those functions.

 Get it from: http://github.com/videlalvaro/xhprof
*/

$funcs = array('Memcache::get', 'array_deep_merge', 'sprintf', 'preg_match');
//only profile $funcs
xhprof_enable(XHPROF_FLAGS_MEMORY, array('ignored_functions' =>  $funcs), false); 

//don't profile $funcs
xhprof_enable(XHPROF_FLAGS_MEMORY, array('ignored_functions' =>  $funcs)); 

//same as above
xhprof_enable(XHPROF_FLAGS_MEMORY, array('ignored_functions' =>  $funcs), true);