Skipping Ticks problem [with Timings]

Hey guys,

I have a Issue that the Server Allways saying " Can’t keep up! Did the system time change, or is the server overloaded? Running 10481ms behind, skipping 209 tick(s)" .
I tried so many things that i found in the internet but nothing helps me to fix this.
In my Timinig i can see where the ticks are skipped but idk how to fix it.

Hope you guys can help me out.
btw sorry for my bad english.

All Information here:

The “can’t keep up” message usually occurs when the server is severely lagging. One common cause of this is unrestrained world generation, which seems to be the case here - look at the impact of the minecraft chunk generator / chunk populate on timings. You can reduce this by using a world border, and pre-generating the world. By the way, your link is a bit broken, it redirects to http://timing/.