Generated a new thin flat world to generate mineshafts above ground. But whenever the game creates new chunks it will freeze for 1-10 seconds. Makes the game unfun to play.
Comments 3
I don't think it is because of the server (hardware). Our server has a powerful AMD Opteron 8-core processor, very fast Harddisk I/O and 32 GB of RAM. When the extreme server lag appears there is at maximum one and a half cores busy. It is a Gnu/Linux Server running the latest Linux kernel 3.9.4 64-bit. Latest Java version (JRE 7 Update 21 64-Bit).
I think the problem is a lot bigger than just to say it's because of hardware performance.
We just tested a bit on different versions, OSes and so on. "Testing" means we (2 players) joined a fresh and clean server without any plugins running, went to gamemode 1 and started flying in different directions (i.e. Player 1 in SOUTH-EAST direction and player 2 in NORTH-WEST). Here are the results:
When we talk about Java we always mean the official Oracle Java.
JRE7u21, Bukkit 1.4.7 Release - After less than a minute there were no new chunks seen in the client, the "last-chunk-border" was crossed. All animals didn't move, no server response when typing in commands and after 2 more minutes players were kicked with a Connection Error and for at least 5 minutes (or even longer) no re-login was possible.
Linux Server as stated above:
JRE6u45, Bukkit 1.4.7 Release - Basically the same as the above.
JRE7u21, Bukkit 1.5.2 #2783 and #2771 - Basically the same as the above.
JRE7u21, Vanilla Minecraft server 1.5.2 - Same as above but problems appeared much earlier!!! So it seems to be a pure Minecraft code problem? I will write more in my conclusion.
Windows 7 64-bit (AMD Phenom II, 6 cores, 8GB RAM, SSD):
JRE7u21, Vanilla Minecraft server 1.5.2: 2 Players could fly a very long time in different directions, but the same problems as above appeared really quickly when a third player joined and also flew into another direction.
CONCLUSION:
From my point of view it doesn't seem to have anything to do with the underlying hardware. It seems that it's just a problem with the vanilla minecraft chunk generation code and maybe some threading stuff. I don't understand why this could be a problem. Chunk generation should be done in different threads than the main thread and once a chunk is generated the main thread should become aware of it and do whatever it needs to do with it.
In the Bukkit Bug Tracker there already exists a similar issue I think you maybe should have a look at it: https://bukkit.atlassian.net/browse/BUKKIT-444
In my opinion it is a serious issue because griefing is easily done when servers don't have any kind of border plugin. Just two griefers who force the server to constantly generate new chunks and everything becomes unplayable.
Is this still a concern in the current Minecraft version? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.