User complaints of lag, help me troubleshoot :>

Users have been complaining of lag at somepoints, and my moderation staff has confirmed it. Sometimes, its on the users side, but sometimes it really is the server.

The server itself is a dedicated box, an Intel quad core Q6600, 4GBram. 100mbit connection, hosted out of San Jose and running Windows Server 2003 64bit.

Here is the .bat run file(updated experimental .bat runfile.):

Code:

@echo off
java -server -XX:+UseConcMarkSweepGC -XX:+UseParNewGC -XX:+DisableExplicitGC -XX:+UseAdaptiveGCBoundary -XX:MaxGCPauseMillis=1000 -XX:+UseGCOverheadLimit -Xnoclassgc -XX:UseSSE=3 -XX:ParallelGCThreads=3 -XX:+UseBiasedLocking -Xms3072M -Xmx3584M -jar craftbukkit.jar 
pause

As you can (probably) see, it is running the 64bit java.

I leave it to use all four cpu cores, sometimes I restrict it to 3 cores if I have something else to do (and dump whatever I have to do on the available core).

Plugins in use:
Dynmap (set to update every four seconds)
LWC
MagicCarpet
Whitelist
WorldEdit
WorldGuard

I can't figure out why it would get lag with 8-10 people. Its odd. I think it may be something related to the garbage collection going on. In looking into the specific commands more, they do make sense to use (accept -jar after -server).

I haven't been able to directly demonstrate the lag itself, but the most common spikes I have seen in watching task manager are when people join or leave.

Any ideas? Only other thing I can think of is limiting the dynmap webpage to 100 connections, but I don't think thats causing the current problems.

Oh, as of this topic being made the server is running craftbukkit #105, and I am about to update that now.

 

I'm fighting lag myself, and with a machine that's much more humble than yours to boot. I found a great post on the minecraft forums a while back that had some good things to help a bit, and they definitely help with the lag.

Some of the things he reccommends didn't work for my server, but it might for yours. Another thing that I do that seems to help a ton (and I'm not sure if it works the same in WinServer OS), is to set the java process' priority to "high" or "realtime" in the Task Manager. The way I do this is to go to the processes tab, and right-click the java.exe process and change the priority there.

I'm a noob at this, so none of this might apply to your situation. >.>;

 

Was that by any chance my guide =D

http://forums.bukkit.org/threads/assigning-more-ram-to-a-server-guide.1432/

Idk if this is applicable to servers.

I'm sure you're not the only one here having lag issues. My guess would be that it's Bukkit itself since it's still being developed.