My server for vanilla 1.14 has been extremely laggy, to the point where the game is not functional at times. Block lag, portal lag, lag when new chunks are loaded, and for the context of this bug report, lag when a player joins the game. Sometimes, when someone joins the server, the server will not be able to keep up, then will crash. Here are two crash reports from the last 24 hours:

https://pastebin.com/qiFzkaeL

https://pastebin.com/Mr1tk2Kg

Here's what the console looks like when the crash occurs:

[00:39:30] User Authenticator #2/INFO: UUID of player CommanderCoopa is c3cec6c0-f7ef-484d-a54c-ae84cde2db23
[00:40:57] [Server Watchdog/FATAL]: A single server tick took 60.00 seconds (should be max 0.05)
[00:39:57] [Server thread/INFO]: com.mojang.authlib.GameProfile@7cee954a[id=c3cec6c0-f7ef-484d-a54c-ae84cde2db23,name=CommanderCoopa,properties={textures=[com.mojang.authlib.properties.Property@548853]},legacy=false] (/68.51.135.139:53391) lost connection: Disconnected
[09:11:39] [Server Watchdog/FATAL]: Considering it to be crashed, server will forcibly shutdown.
[09:11:39] [Server thread/WARN]: Can't keep up! Is the server overloaded? Running 30701987ms or 614039 ticks behind
[09:11:40] [Server Watchdog/ERROR]: This crash report has been saved to: C:\Users\Christofin\Desktop\Server Stuff\Vanilla\.\crash-reports\crash-2019-04-28_09.11.40-server.txt

I'm running the server on hardware more than capable: my CPU is a i7 7700k clocked at 4.5GHz, and the world is brand new with a few villagers at spawn and not much else that would cause lag compared to an established world. No more than 7 players have ever been on at once.