Server keep going "read time out"

Posted already but failed with thread name and idk how to remove threads^^

When my server has been on for a while it says "Read time out" in console and none can join.
the machine hosting my server is a windows server 2008 x64 STD, java version is latest 7.
and the server has 1.5GB ram. Im using bukkit RB 1337

This is what I find in console except "Read time out"

Code:

2011-11-06 13:51:11 [SEVERE] java.util.ConcurrentModificationException
2011-11-06 13:51:11 [SEVERE]     at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
2011-11-06 13:51:11 [SEVERE]     at java.util.ArrayList$Itr.next(Unknown Source)
2011-11-06 13:51:11 [SEVERE]     at net.minecraft.server.World.tickEntities(World.java:1109)
2011-11-06 13:51:11 [SEVERE]     at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:467)
2011-11-06 13:51:11 [SEVERE]     at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:374)
2011-11-06 13:51:11 [SEVERE]     at net.minecraft.server.ThreadServerApplication.run(SourceFile:417)
2011-11-06 13:51:11 [SEVERE] Unexpected exception
java.util.ConcurrentModificationException
    at java.util.ArrayList$Itr.checkForComodification(Unknown Source)
    at java.util.ArrayList$Itr.next(Unknown Source)
    at net.minecraft.server.World.tickEntities(World.java:1109)
    at net.minecraft.server.MinecraftServer.h(MinecraftServer.java:467)
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:374)
    at net.minecraft.server.ThreadServerApplication.run(SourceFile:417)

 

Seems like too many mobs spawned. Did you try doing /butcher 500?

 

You mean I should do the command when the server does "Read time out"?
I have three worlds on the server. Is that a problem?

 

No, you should try that command sometimes.

But it seems like it may be the mutliworld problem - mobs spawned x 3 words = a lot of mobs.
1,5 GB of RAM is really, really low for multiworld server.

 

ok.. u think its gonna work with a moblimiter?

 

Maybe - I don't know. You should try and see if it works.

 

I hope you don't mind me bothering you, but how many worlds could one run with 8gb of dedicated RAM and 24 gb Burst? I've asked this question before but no one seemed to know...

 

@Orcem12
Hmm, honestly, it depends on how far are people from each other. It's like one world, but with people all over the map.
It also depends on your HDD speed, number of players, how big is your world, etc.
I'd say that 5 worlds would be max for ~50, 60 players. (I can be REALLY wrong now - I did NO research, you have to test it by yourself)

 

@Acrobot
I'm not to sure about my HDD speed, all my maps are limited using a world border plugin. It's a 400 slot server from my host I bought and we run 247 average with little to no lag. The players that stay on the server usually stick together in towns or guilds so they aren't spread out my main map, my nether, and creative lands are all limited. I think my main map is a 5000 radius and my nether and creative are 1000. I wanted to add one more with mob spawning off and animal spawning and making an adventure map featuring a "Jail" world.

 

@Orcem12
I'd say that ~10 worlds then

 

XD Thanks ^.^ finally someone gave me somewhat of an imput

 

Well people can't answer that easily. It's more of a guess. The amount of players/worlds a server can handle depends on tons of factors. Even then it's still a guess... So how about you just try and see if it works? The only way to tell.

 

It's a good point you've made and I know it's just a guess that's why I said "somewhat of an input" I'll try it out.