Speed Up p2 theme for users number more than 20000 users

To speed up p2 theme for more than 20000 users , disabled all “at name” / @username hooks in functions.php

/* disabled by me too, slow ...
if ( !is_admin() ) add_filter( 'the_content', 'p2_at_names' ); // hook into content
if ( !is_admin() ) add_filter( 'comment_text', 'p2_at_names' ); // hook into comment text
*/

and …

/* disabled by me, too slow
add_filter( 'the_content', 'p2_at_name_highlight' );
add_filter( 'comment_text', 'p2_at_name_highlight' );
*/