Is the FTB server multi threaded or single threaded

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ebopalisesy

New Member
Jul 29, 2019
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I have a computer that can run in 4-thread or 8-thread mode. However, the efficiency is 33% less per thread when I run it in 8-thread mode, and I want my server to run as fast as possible, so I was wondering if the FTB server is single threaded or multi threaded. I have noticed that when generating terrain in Linux, the server seemed to be using only one core. However, when I load up orespawn and spawn 20 kings, it seems to be using all threads. I also know that minecraft's chunk loading was recently made multithreaded within vanilla.
 
Minecraft doesn't make much use of multiple threads until version 1.8.
4 thread mode is probably your best bet.

Completely agree. For MC 1.7.10, my 4-core dedicated server never spikes higher than ~250% CPU. It's usually between 10% (no players) and 120% (handful of players with 1 exploring).

In others words, it uses at *most* 2.5 cores/threads and has a hard time taking advantage of more than a single thread/core. As such, I don't hyperthread.
 
Ok. Good to know, as I'm still getting lag with a 4790k... hopefully turning off hypertheading will help.
 
Which pack, how many players, and how much RAM ?

I'm using Infitech2 (fairly heavy pack), 3 to 4 players, and 16GB physical RAM. Here are my Java args:

Code:
java -Xmx8192M -Xms4096M -XX:PermSize=256m -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalPacing -XX:ParallelGCThreads=4 -XX:+AggressiveOpts -XX:NewRatio=3 -XX:SurvivorRatio=3 -XX:TargetSurvivorRatio=80 -XX:MaxTenuringThreshold=8 -XX:+UseParNewGC -XX:MaxGCPauseMillis=10 -XX:GCPauseIntervalMillis=50 -XX:MaxGCMinorPauseMillis=7 -XX:+ExplicitGCInvokesConcurrent -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=60 -XX:+BindGCTaskThreadsToCPUs -Xnoclassgc -Dfml.queryResult=confirm -jar Infinity2.jar nogui
 
And, if you haven't already, run Opis to see what's chewing up CPU. 90% of my CPU is consumed by vanilla MC mobs. Mojang 1.7 code is terrible.
 
You also have to consider what mods do. Not only the vanialla FTB server.
Some mods create their own threads to do things asynchronously from the servers main thread.
However. If all threads suffer a 33% malus if the CPU runs in 8-thread-mode, I would try 4-thread-mode first.
because the main thread is the critical one and needs full performance.
Async threads of mods usually are not so depedent of speed. They just need to do their work in the background without bothering the main threads program flow.

(What do you mean with "efficiency" in this case?)
 
Vanilla squids are an issue on my server... I am using a different pack with EnderIO which has a config to turn them off completely. I than use minetweaker to add ink sacs to grass drops... it's a bit odd but it works
 
I CANT HELP IT! Seriously when I did a /cofh kill all squid it nuked over 300 on my SSP world