What is mdworker Working On Right Now

I just did a clean install of OSX Mavericks, after migrated important via Migration Assistant, the mdworker on OSX Mavericks is busy indexing stuff.

You will see a bunch of mdworker(s) doing their work in Activity Monitor

Screen Shot 2014-03-20 at 12.29.30 AM

If you want to find out what are mdworker(s) working on, can try this command in the terminal

If you found out there are folders you don’t want Spotlight to index, can add it into Privacy tab on Spotlight’s preference.