Server frequently runs 2556ms behind and skips 50 ticks about every minute

After I updated my mc server.jar to the latest snapshot, it keeps on giving me the message:
Can't keep up! Did the system time change, or is the server overloaded? Running 2556ms behind, skipping 51 tick(s).

Once it displays the message I notice that the average tick skyrockets from 1-2 ms to 25+ ms.

I am running the latest 64 bit java, and have the server running off of 4 gb of ram. I have tried multiple different worlds, all of which replicate the same problem. My computer has an i7 4770 processor, and it has handled previous snapshots perfectly. I have no clue why it keeps skipping ticks, any help would be appreciated.