Server Crash, Occasional player resets

[Maimfromaway]

I host a small FTB Ultimate server (>12 people) for myself and my friends. However, as of late, we've been plagued with server crashes. Occasionally, players will have their entire inventory deleted and will be respawned at the server spawn.

-Windows 7 64 bit
-FTB Ultimate vanilla v1.1.2
-I don't remember the exact specs of the server, but they should be adequate- 4 gigs of RAM, quad-core 3.2 GHz Intel i5 CPU, adequate HDD space, etc.

I run the server with the following "run.bat" file:

java -Xms1G -Xmx1G -jar ftbserver.jar

I can provide the error seen by the players as it happens again- in the server log, it shows up as follows:

[WARNING] Maimfromaway moved wrongly!
[WARNING] MCGamer42 moved too quickly! -1.2707130015205053,0.0,13.603322730254376 (1.2707130015205053, 0.0784000015258789, 13.603322730254376)
[WARNING] Can't keep up! Did the system time change, or is the server overloaded?
[INFO] Maimfromaway lost connection: disconnect.genericReason
[INFO] MCGamer42 lost connection: disconnect.genericReason
[WARNING] Can't keep up! Did the system time change, or is the server overloaded?

This incident resulted in Maimfromaway (me) being reset and returned to spawn. At the time I was doing nothing.

Any idea what could be causing this issue?

 

[Eyamaz]

Exactly what it says. Your computer can't keep up. I'm assuming your playing from the same computer your hosting from. You don't have the specs for that. Vanilla, yes. FTB, no.

 

[Maimfromaway]

Actually, I'm playing off of a different computer on the same network. I've hosted Tekkit servers off of that PC before without issue- is FTB really that much more resource intensive? Also, does that error frequently cause players to lose inventory? That's really the issue I'm concerned about.

 

[Eyamaz]

Ftb ultimate is EXTREMELY cpu and memory intensive. You want a minimum of 512mb per person connecting to the server for memory.

As far as the inventory wipes, it's not a common occurrence. Yet I've seen all sorts of strange issues happen from ultimate servers if the server can't handle it.

 

[cjm721]

Mods are mods if you want to talk about CPU resources IC2 on tekkit is the same as IC2 on FTB. As for what is causing the resets my guess would be not allocating enough ram as when the ram starts to get full the garbage collector runs more often and it could accidentally remove an active file.

As for Eyamaz you talking MB or Mb, as for me it be closer to 512Mb per person then MB per person. Changing what GC you use and how you handle chunkloaders has a huge effect on amount of ram an adverage person uses.

 

[Eyamaz]

MB. Client side, ultimate can take up to 2.7GB+ of ram. From what I've noticed of people posting, it's an average of about 1.5MB.

Server side, your looking at about 256MB to 512MB of ram per player, unless everyone shares a base. This is over time btw, not from the start.

 

[cjm721]

And I am using 3.8GB for 23 people at this very second. Use the new garbage collector and you will find its much more efficient.

 

[Eyamaz]

And I am using 3.8GB for 23 people at this very second. Use the new garbage collector and you will find its much more efficient.

I do use g1gc, and yes, it does help keep your ram usage down a lot. You also have to remember I'm talking about a stock ultimate server. No additional jvm arguments. Using jrocket also dramatically increases performance, but I was also told a couple mods were not compatible with it. No, Idk which ones.

 

[cjm721]

Stock ultimate server will take the additional arguments. The arguments are for the JVM not the minecraft server and can just as important if not more then what you do to the physical minecraft server.

 

[Eyamaz]

Ok, let me spell this out.

The ram usage I listed above is when running an ultimate server and not adding any additional jvm arguments when you start the server.

 

[cjm721]

Well if your trying to maximize what you have you should account for what you can do.