Keep having High CPU Problems, nothing works. Need you help!

Hello Bukkit Community,


First off, I'd like to introduce myself. I'm FewSome and I'm running, like many different people here, my own MineCraft Servers for my own small community. Sometimes "1 Post" User are not very welcome, because they seem like not supporting the community at all? Maybe I'm wrong about that, but let me tell you that I've been reading these forums from the very beginning when I first saw the "CraftBukkit" Thread on some Forum I can't quite remeber. I never needed to post or ask questions, because I have the opinion that with some common sense, reading "skills" and linux knowlage it's pretty easy to set-up and maintain a BukkitServer. One HUGE Thanks goes to all the plugin Coders that do very good work with documentarys, wikis, tutorial videos and so on. I often think ppl would be able to solve 90% of their problems just by reading the thread or the specific plugin documentary.




I'm the owner of two root servers and a small v-server for forum, voice server etc. but for a while now I'm having very serious problems with bukkit and my root servers. And im finally out of answers and cant find anything on this topic in this forum or with google.


My problem is the CPU Usage with Bukkit on the Servers. It's always through the roof and coses massive lags. The value from "top" is always at 100 – 150%. Memory is totaly fine. 20-40% MAX.


The Server can barely hold 10-15 players, from there on it's just very very laggy.


I've tried different things to isolate the problem.


Diffent Bukkit builds with different Setups (with plugins, without plugins, classic server, different worlds, fresh world, different start options, different bukkit builds etc.)


And without plugins the CPU usage is under 100% with 20 players but still at 80% and then it might be able to hold another 10 players, so that would make 30 players top and im pretty sure the server can hold much more in theory.


The best results I can archive are with the ClassicServer Software and Bukkit WithoutPlugins.


What made a little difference was using OpenJDK Runtime Environment istead of the SUN JAVA.
The Server can now hold about 15-20 ppl with minor lags but constant "cant keep ups".




Normaly Id say "okay it's java, its custom server software on a beta game, so dont wonder"
But there are very big community like Buxville, Super Earth, BattleCraft, GodCraft or MeinKraft and they can handle up to 100 players. I'm getting depressed over that.




My Serverstats are:


Prozessor
AMD Athlon PII X4 Quad-Core 4x 2,3 GHz
42 GB DDR3 ECC
2 x 1.500 GB
SATA II, 5.400upm, 8MB
RAID RAID 1 per Software
Switchport 100 MBit over 150 GBit
(Dedicated Server from a hoster)




OS:


Debian 5.0 - minimal - 64bit
Linux version 2.6.32-bpo.5-amd64 (Debian 2.6.32-30~bpo50+1) ([email protected]) (gcc version 4.3.2 (Debian 4.3.2-1.1) ) #1 SMP Mon Jan 17 18:24:45 UTC 2011



Java:


java version "1.6.0_22"
Java(TM) SE Runtime Environment (build 1.6.0_22-b04)
Java HotSpot(TM) 64-Bit Server VM (build 17.1-b03, mixed mode)




java version "1.6.0_18"
OpenJDK Runtime Environment (IcedTea6 1.8.3) (6b18-1.8.3-2~lenny1)
OpenJDK 64-Bit Server VM (build 16.0-b13, mixed mode)




CraftBukkit: 766 (733, 739, 740)
Tested all recommended and not recommended builds. No mentionable difference, I think.

All Plugins that can use MySQL have their own MySQL Database. Is that okay?



My Startshell:

1.
#!/bin/bash
clear
clear
screen -S server1 java -Xmx12G -Xms12G -jar craftbukkit-0.0.1-SNAPSHOT.jar


and



2.

#!/bin/bash
clear
screen -dmS server1 java -server -d64 \
-Xmx10G -Xms5G \
-XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+CMSIncrementalPacing -XXarallelGCThreads=2 -XX:+AggressiveOpts \
-jar craftbukkit-0.0.1-SNAPSHOT.jar
(Some BukkitForum user postet it)


With these JAVA start Options the CPU Usage seems to be better but I can't use ist because I've a huge problem with Physics while using these options. Physics like water are very slow.






I tried to be as specific as possible and I hope some experienced server admins will bother to answer and maybe can help me I'd be so happy!




Thank you guys very much and sorry for the endless post,
Fewsome


P.S I tried all these things with two complete physical different root servers, so its not the server. Maybe the AMD CPU is just to weak? (nouuu)

 

Maybe try sun java 1.6.0_25 as there was a performance release not too long ago that may help.

And maybe try some more java arguments from here: http://forums.bukkit.org/threads/ho...24gb-dedicated-server.3967/page-2#post-184208