Problem/Bug Rollbacks when chunk generating

Hi,

I have a small minecraft server (something like 30 players at the same time)
I have a big physical server (2xXeron E5-2650 2.6Ghz with 32 threads, 200Go Ram, SSD)

But i don't manage to get it work without rollbacks
I have a lot of messages like this in the console :

Plugins (50): HideStream, Kits, WorldEdit, FarmProtect, AutoShutdown, WhiteMessage, Buycraft, Vault, PermissionsEx, Multiverse-Core, HealthBar, DACv2, CookieMonster, WorldGuard, dynmap, Disabler, XpRank, TimingsParser, TNTRun, ReportRTS, ChestCommands, pvparena, Lockette, RedstoneClockDetector, ProtocolLib, HolographicDisplays, Herochat, Stats, WGCustomFlags, MobArena, CustomMobs, Essentials, SimpleRegionMarket, Jobs, NoCheatPlus, EssentialsSpawn, Multiverse-Inventories, SignShop, JSONAPI, NoEnderpearl, EssentialsAntiBuild, PayDay, AuthMe, WGRegionEffects, BKCommonLib, EssentialsChat, BattleArena, ArenaSpleef, VanishNoPacket, NoLagg


NoLagg Exam :

Timings : http://goo.gl/khTy6T

I think i have only rollbacks when someone is geneating chunks, but i don't know why
I already try to remove a lot of plugins, like dynmap, orebfuscator, nocheat, ... but everytime this doesn't change anything

I also have bug when generating worlds, like tree with missing leaves blocking you
And when you logoff/login leaves are now here. I don't know if there is a link between the two

I took a bigger server recently, because CPU on one thread was at 100%, so i was thinking that the server was too cheap, but there is no change. CPU is going to 100% with the new server too

Do you have an idea ?
Is there a way to add parameter to the command line to ask bukkit to use multi thread ? Because the server has 1 or 2 in load average (only one thread at 100%), but we have lag ingame ...

Thanks

 

You are most likely overcharging your server.
Whenever the CPU is on 100% it means that the chunk loading / player ratio is not right.
Whenever the computer has more commands then it can handle it either skips them or does them in parts.

There are basically only two fixes for this;
- You upgrade your server to more RAM, which might cost money but honestly is the best solution here.
- Or you install AutoSaveWorld ( http://dev.bukkit.org/bukkit-plugins/autosaveworld/ ) and setup a worldsave every minute or so. This is just a temporay fix, considering the CPU will stay on 100%, and therefor is running over it's capacity.

 

Hi,

I don't understand your answer

- Uprade RAM : I have 200G of ram, java Xmx is set to 30G, and server usage never exceed 10G, not sure there is a lot of better server ...
- Autosaveworld : I don't see why adding a save of world will decrease CPU Usage, for me it will increase it

Thanks

 

Hello,
Whenever your CPU reaches 100% it means that your computer is overloaded, whether it's because of lack of GB or wrongly setup plugins.
I honestly don't know your full setup- but something is wrong when the CPU is on 100%.

 

Maybe try it without NoLagg: being blocked because the server hasn't yet send all chunk data properly sounds like an issue with the chunk sending, and NoLagg has features which affect exactly this.

Also if the issue is really only when generating fresh chunks: you could let the server pre-generate all chunks in a certain radius and block players from moving outside that radius. The plugin WorldBorder can do that.

Though timeouts of 10 seconds really sounds like a complete different issue. Do you have any plugins which affect the scoreboard? Which server version are you running on? 1.7.10 or later?

If yes there was some change in the past which caused older/not-updated plugins which set custom scores in scoreboards to cause an enormous amount of lag everytime they attempt to modify the scoreboard.

 

I already try without Nolagg, but i doesn't change anything.
If i well remember the difference is that with nolagg i have a small rollback very often, as without i have a big rollback less often (like 40 ticks every minute versus 200 ticks every 5min)
If you think it could be that i could try again to be sure

I will check Worldborder features, thanks

I'm running Bukkit 1.7.2-R0.3 and i don't have any plugin with a link with scoreboard i think

Maybe it's not only one cause, because i'm looking on it since a long time and i don't find a solution

I will try to fill the world with worldborder tomorrow
I will let you know

EDIT by Timtower: merged posts

 

Your server needs to restart now and then. NOT RELOADED, restarted!
Download an auto-restart plugin.
http://dev.bukkit.org/bukkit-plugins/auto-shutdown/

 

I already have this plugin, with a reboot every 3 hours
Don't see a big change before and after reboot

 

Hi,

So i have generated the worlds with WorldBorder since 2 days, so normally no new chunks have to be calculated
I always have a lot of "Can't keep up .." lines in log, but rollback are not felt by players, so it seems to be ok
I'm mining since 30min without rollback, which was impossible before

But i have a big problem since today, sometimes all players are kicked from server
Already havec this 3 times since one hour

Nothing in logs
Do you have an idea ? Maybe the world generated by the WorldBorder plugin is corrupt ?

Thanks

 

What exactly do you mean by "rollbacks" ? I don't understand what you mean by that (do you have to roll back the entire world map, do individual chunks save an old state instead of the latest, do players get set back while moving, possibly others?)...


Edit: One core heating up could be a heavy task or usually indicates that the main thread is too busy, the latter backed up by the impression of ingame-lag. Given the nolagg overview, you have pretty regular spikes by chunk loading, which i can't really explain, given reasonably low player count + ssd + ram. Did you take timings for a while (please don't use URL shorteners )?