I run a 1.8.3 vanila Minecraft server.

The problem with it is that it's being overloaded by one specific user (let's call him U) who runs a 1.8.3 vanila Minecraft client w/o any tweaks on Windows.

This is how the server feels before U logs in:

server console

and that's just after it: server console

The server continues being overloaded and skipping ticks while U is online:

server console

and starts feeling well immediately after U disconnects:

server console

The server on the screenshots is running only U and another player. It may run extra 2 people w/o any changes if U is not online. The odd stuff is only happening in U's client log:


The server is being launched like this (it's on a machine that has 5 gigs of RAM):

java -Xmx4096M -Xms4096M -jar minecraft_server.1.8.3.jar nogui
  • 3
    You've gone to the effort of not naming this player in your written post, but then uploaded images with their name displayed in it...
    – JonK
    Commented Mar 14, 2015 at 16:30
  • 2
    If you travel to this player's base of operations when they're not logged in, does the server misbehave in the same way?
    – JonK
    Commented Mar 14, 2015 at 16:33
  • @JonK, I renamed the player in the post just because I was lazy to write "the player" all the time :) He didn't mind to show the nickname. We share the same base with him so I was actually there. Commented Mar 14, 2015 at 16:38
  • 2
    Perhaps try backing up and then temporarily deleting their player.dat to see if the problem persists; it should help work out whether it's their client or player file causing the problem. Also, have you got any command blocks doing anything?
    – SirBenet
    Commented Mar 14, 2015 at 17:19
  • @colorfusion, thanks for your suggestion, I'll try it out. We don't have command blocks at all. Commented Mar 14, 2015 at 23:09

3 Answers 3


Most likely it's not the client, but the area he is building in. If something about his structure causes high server load (such as a large, complicated redstone circuit), it will only lag the server when that chunk is loaded. If he's building somewhere far away from spawn, his chunk will only be loaded when he is online, because no one else can find it.

You can easily test this theory by teleporting to his logout location and seeing if the lag starts up again.


Looks like his client may be misbehaving. Try having him create a new profile in the launcher and connect with that. From the logs, it looks like he's causing an error and slowing down the server by his client skipping ticks. Spigot worked because of how Spigot treats clients that do this.


try using this command to launch the server

java -Xmx1G -Xms200M -jar minecraft_server.1.8.3.jar nogui

I had the same problem and I wasn't giving the server enough memory to run with any amount of players on it. You need to give your server at least 1GB per player, your only giving it .5GB (5000MB).

  • Why will this fix it? What will it do?
    – Frank
    Commented Mar 31, 2015 at 16:18
  • It will allow the server to use more memory the Xmx is the max RAM you are allowing the server to use the more you allow it to use the faster it will run
    – Eisler 485
    Commented Mar 31, 2015 at 16:23
  • 1
    That allows it to use more memory, but how does that solve the problem the asker is having? You need to explain that as part of your answer.
    – Frank
    Commented Mar 31, 2015 at 16:24

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .