I'm using 10.8.2. I've observed today in the activity monitor that "mdworker" is using 100% of my CPU. When I click the 'inspect' button it showed "launchd" as the parent process for "mdworker". My CPU temperature is in between 70 to 80 celcius. This is going on from the last 3-4 hours. My harddisk has almost 75% free space of the total space(500GB). The spotlight search icon in the menu bar is blank(No dot in it) i.e., spotlight is not indexing. Why is this happening even though when spotlight is not indexing? I've not connected or mounted any external drives. I've installed skydrive app a few days ago. I've updated to 10.8.2 last night. And I've also installed the Macbook pro 2012 firmware update released last night for non retina mid 2012 models.