title: MYSQL suddenly uses CPU even when no one user is connected to Mysql
body: <p>Site is an ecommerce site: 5 Million records in table
  Two servers: one for webserver and other contains mysql
  Search is happenning through Sphinx server. So search queries do not come to MySQL</p>
  
  <p>Mysql configuration: Dual Quad Core Zeoo 2.0, 146 GB, 16 GB RAM.
  Webserver configuration: Dual Quad Core Zeoo 2.0, 146 GB, 16 GB RAM.</p>
  
  <p>For past four days I find MySQL is using CPU continuously for at least 6-7 hours in a day. It becomes normal after that. Even if I restart, it doesnt stop. It again uses CPU in 2 to 3 mins. I even tried stopping Apache and made sure no one is connecting to Mysql.</p>