kdevtmpfsi question

[tim wade]

  18817 user       20   0 3075708   2.3g      0 S 392.7  29.6  84:30.28 
kdevtmpfsi

As you see above (top output), kdevtmpfsi consumes 2.3g Ram and a lot of 
CPU (392%).
What's it then?
Thank you in advance.