I have an Wordpress website with more than 219k of posts, and everytime when I publish something my CPU/MySQL usage go to 100%.
I really don't know why, because my entire website stay on 6% all day of usage and only spikes at a new post is published.
Yes, I use w3 super cache, but the problem is on the wp-admin itself! I've used the mysqltuner for optimizing the MySQL... But, like I already said, the problem only occurs when a new post is published.
I use two clouds on Amazon AWS for hosting the blog. The MySQL cloud is m1.medium and the Web Server is m1.xlarge.
Here is the graphics of my CPU's, as you can see, I have spikes at the same time on both clouds... These spikes occurs exactly on the time when I publish a new post. The green line is the MySQL and the blue line is the Web server.
Here you can see the graphic: http://i.stack.imgur.com/PReQP.png
If no one can help me with this situation, please, I want something to "inspectate" the code... The entire scruture of Wordpress is so ugly that I can't understand how new posts works. I want to debug the queries/functions or something like that.