one can test website load time and analyse content by tools like http://tools.pingdom.com/fpt/ or webpagetest.org
but regarding Wordpress, i see huge time to first byte (or time untill webpage starts loading), i think cause is wordpress plugins. Also in cpanel, i see my index.php script takes 60% of 2.3Ghz cpu to load, which i consider tooo much.

So question is, is there any Wordpress plugin, that analyses times and job done by plugins during wordpress webpage load? I mean so i identiffy bad plugins etc..

update: here is one wp plugin: "P3 (Plugin Performance Profiler)" - https://wordpress.org/plugins/p3-profiler/