The "Can't keep up!" error just happened out of nowhere

[JunkyPic]

Starting as of about 2 hours ago, I keep getting this error:"2012-08-29 19:18:11 [WARNING] Can't keep up! Did the system time change, or is the server overloaded?".

I've poked around and nothing that I've come across seems to help.

Some people suggested that this is caused by the server hardware.

I don't think this may be the issue, here's the hardware that I'm running the server on:

Processor - Intel Xeon E3-1230 4 Cores (8 HT Cores)

RAM - 16 GB DDR3

HDD - 120 GB SSD

Internetz speed - 100Mbps Unmetered connection.

Running on Ubuntu Server.

Other people suggested that this is caused by to little memory allocated to Tekkit.

I've allocated 13GB, so that's shouldn't be the problem.

Again, others suggested that there are way to many people on the server.

There were 15 people online when this started to happen.

I use Java 7 JRE, as far as I know everything is up to date.

List of plugins I use:

AutoMessage

BorderGuard

CoreProtect

Dynmap

Essentials

ItemStacker

LagMeter

LWC

WorldEdit

Other than that I can't think of anything else.

So far it hasn't hindered the server's performance(as far as I can tell anyway), but I fear that it may do so if this keeps up.

If anybody has encountered this problem before, how did they fix it?

[greedseed]

it depends on a lot of factors

it can even be a player pumping 5K of items threw BC pipes that makes there come up. Or it can be mods running wild. That has already happend so give is some more info about what mods you got running and or if anything is banned that can couse lags

[Phuriousgeorge]

Also, do you have custom Java arguments in your launch.bat? I've seen several people attempt to tweak theirs and come back with a few minor syntax errors or just plain bad setups.

[Torezu]

I would not have assigned 13GB to the server, tbh. That just doesn't leave enough for Java to use its garbage disposal routines. Maybe 10?

[xXMineFabiXx]

The Lag can also be caused by Worldanchors used with Quarrys (big Quarrys) or Quarrys without a empty chest (All items drop on floor=lag)