FTB Server-side Lag

[luigimario211]

Every time I run a server, whether it is Ultimate or Unleashed, the mobs and players seem to lag in movement. I tested this on a cow and it seems that it (the cow) is taking baby steps when it runs round in a circle. There is also a slight delay when they are hit as well. This seems to happen when I run it off my local network (no Internet), so bandwidth should not be affected. As soon as I start a brand new world, it just lags heavily. It is definitely server side as my friend who also plays on the same network, is having the same problem. Java is fully updated, not using the hosted computer, not a RAM issue as I have allocated 2 GB. In the server log, there are no errors in the console either. I don't experience any client lag. Firewall is definitely not the problem. Breaking and placing blocks is absolutely fine!

Maybe I am having tick rate issues? How do I find out about TPS without using any plugins? Is it the 'Avg. ticks' counter in the 'ftbserver.jar' console? Because that is 0.6 and I'm pretty sure that the server wouldn't run at all.

I used to run a Tekkit Classic private server for 5 people for a while and there were no issues then. I also used to run a Bukkit server with many plugins and no issues either. I have tried testing FTB Lite, even that has lag.

Sorry if this is too much information but I'm trying to narrow this problem down to one solution.

Here are the computer host details:
OS: Windows 7 Home Premium 64-bit
Processor: Intel Core i3 CPU 540 @ 3.07 GHz (4 CPUs) ~3.1 GHz
Memory: 4096 MB RAM
Java: Version 1.7 Update 25 64-bit

I have also looked at the troubleshooting guide and there is nothing there to help me. I have tried everything and I am completely STUMPED! Need a fix ASAP.

 

[luigimario211]

Anyone know the answer? Waited a day and a half and still no replies... and yet other threads have received an answer straight away. Oh well, atleast I tried looking for help...

 

[Eyamaz]

can you post the contents of your startup file?

 

[luigimario211]

java -Xms512M -Xmx2G -jar ftbserver.jar

 

[Eyamaz]

java -Xms2G -Xmx2G -XX:+UseConcMarkSweepGC -XX:MaxGCPauseMillis=40 -XX:GCPauseIntervalMillis=150 -jar ftbserver.jar nogui

try that for a bit, see if it helps.

 

[luigimario211]

Thank you kind sir, that has fixed the lag. Now another problem, not so high prioritized, is, why does my operators file reset every time I restart the server? It seems to generate a new one. This is not a big problem, it is just tedious re-opping myself through the console every time.

 

[Eyamaz]

Hrm. Idk, I've never encountered that issue before.

 

[luigimario211]

Oh well, doesn't matter, thanks for helping anyway!

 

[TheSandwichMakr]

Set the ops file to read-only and it will be able to read it but not remove it, however you will also have to change back to read-write every time you want to modify it.