Very high CPU usage on Craftbukkit #1337

Hi. I'm new on this forum.
I've problem with my Craftbukkit #1337 that uses 120%-150% of CPU when 1 player is logged in.

Hardware specification:
Intel Xeon 2,8GHz (Dual-Core)
Ram 4Gb DDRII ECC
HDD: 32Gb SCSI

Server is running on Debian Squeeze x64, Java version 7:

Code:

Linux alphasrvr 2.6.32-5-amd64 #1 SMP Fri Sep 9 20:23:16 UTC 2011 x86_64 GNU/Linux
java version "1.7.0"
Java(TM) SE Runtime Environment (build 1.7.0-b147)
Java HotSpot(TM) 64-Bit Server VM (build 21.0-b17, mixed mode)

To run Craftbukkit I'm using command:

Code:

java -d64 -Xincgc -Xmx4G -jar craftbukkit.jar nogui

I've tried installing older and newer versions of Craftbukkit (#1317 - #1344), running without plugins before I posted here, but the problem repeated.

On vanilla Minecraft server max. CPU load is 50%.

Screenshot from "top" in attachments.

Thanks in advance, rosal0

ps. The first core is 90% loaded and second core is 20%-50% loaded.
ps2. Sorry for my English. If I made a mistake - sorry.

 

We are also seeing this issue, since we upgraded to 1.8.1 it has increased mentally, attached are some graphs of before and after


Sorry edit button wouldnt work right





EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Do you have any plugins installed. Please list them. Try to boot the server with out any. Also you may have a corrupt map, try to boot with a new map and see if that works.
Let me know iff these worked/didnt work. Please quote me in a response.

 

I've tried to run server without plugins, but there was the same effect.

I discovered what was the problem - old map. On new generated map and 6 players online, CPU load is max. 92%, average ~40% ON FIRST CORE!!! Second core is 100% idle.

I took screenshot when 1 player was online (in attachments).

To AskewDread:
If you have the same problem - try generating new map using seed from old map and move buildings, chests itp. to new map.

I can list plugins if somebody want.

Thanks for help!

 

i had this problem for awhile however it went away after awhile. I simply attributed it to the ammount of water in the game now.... I have always had a problem when first generating terrain with lots of water in it.

 

We have the following plugins, would prefer not to have to create a new map.... as its a huge thing to do.
17:01:15 [INFO] Plugins: WirelessRedstone, Spout, WorldEdit, CraftBookVehicles, HeroicDeath, PermissionsEx, nSpleef, WorldGuard, CraftBookCircuits, GlobalChestBanking, CommandBook, xAuth, CraftBookMechanisms, RAM, CraftBookCommon, ChatManager, HawkEye, dynmap

ive noticed looking at the graphs, its ok for 6 hours after the restart and then it starts building

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

hmm it appears it was dynmap causing an issue, i have removed it and now its averegaing about 30%, so will tune it down a bit and make it update less often and might fix it thanks guys

 

Yeah, I removed it temporarily from my servers as it was chewing up the CPU and trashing the TPS. I haven't taken the time to try again with some tweaking.

 

i changed it to update every 15 seconds instead of 1 and changed what it updates on and it seems to have fixed it