FTB Direwolf20 Server Lag?

[PhantomOC]

I started up a server for me and my (1) friend. I was getting some error in the console saying "[Warning] Can't keep up! Did the system time change or is the server overloaded?" I see this message a lot even when I host servers that don't lag. The problem is we are getting some pretty bad block lag. My PC specs are:

AMD FX 8320 3.50GHz
AMD Radeon R7 360 2GB OC Edition
8GB Ram (But I use around 16GB Ram on the server)
1TB hard Drive

This lag has caused us to stop playing FTB Direwolf20 on the server. Also this is a home hosted server. Can someone please help me? Thank you!

EDIT: I was using Direwolf20 1.7.10 Version.

 

[Goshen]

do /cofh tps and see if it tells you which dim is causing issues

We had an issue where someone released imbued fire from thaumcraft and it went rampaging out of control in the nether without stopping, it brought the server to its knees. Wiping the Nether fixed the issue. That nasty stuff is banned on all of our servers now.