Cached ram memory

I've only seen this since playing battlefield 1. My cached ram Data keep going up and it isn't clearing I just upgraded to 16gb ram and currently I have 10gb in cached. Is there a reason it isn't resetting? Is this normal? Is there something I need to check? I've never seen this happen it any other game I've played before.

I5-3570 3.4ghz
16gb ram
G5x 950 2gb
Lastest drivers