Bukkit

Pastebin link to your Config (I will ignore your ticket if it doesn't contain this:
http://pastebin.com/2ShRhMxn

What steps will reproduce the problem?
1. /lagg check
2. /lagg unloadchunks
3. /lagg check

What is the expected output? What do you see instead?
[8:33:02 PM] *                          (Server Status)                           *
[8:33:02 PM]    Items on the ground: 3237
[8:33:02 PM]    Mobs alive: 6027
[8:33:02 PM]    Chunks loaded: 19299
[8:33:02 PM]    Active hoppers: 27
[8:33:02 PM]    Idle hoppers: 45
[8:33:02 PM]    Active mob spawners: 367
[8:33:02 PM]    Current TPS: -240.28
[8:33:02 PM]    RAM Usage: 5100/15564MB
[8:33:02 PM]    Players online: 10
[8:33:02 PM] *                                                                             *
[8:33:44 PM] [ClearLag] 18119 chunks have been unloaded!
[8:33:52 PM] *                          (Server Status)                           *
[8:33:52 PM]    Items on the ground: 3211
[8:33:52 PM]    Mobs alive: 6063
[8:33:52 PM]    Chunks loaded: 19342
[8:33:52 PM]    Active hoppers: 27
[8:33:52 PM]    Idle hoppers: 45
[8:33:52 PM]    Active mob spawners: 369
[8:33:52 PM]    Current TPS: -240.28
[8:33:52 PM]    RAM Usage: 5004/15564MB
[8:33:52 PM]    Players online: 10
[8:33:52 PM] *                                                                             *

What version of the product are you using?
2.8.4

Do you have an error log of what happened?
no errors produced

Please provide any additional information below.
So, for some reason chunks in the world do not unload when lagg unloadchuncks is executed. It says it unloaded them, but they are still there.

regards,
ruphskunk

It's possible a plugin/mod is preventing them from unloading. Clearlag uses Bukkit API to unload chunks.

I'm sure you're running a modded server, and those mods do not allow the chunks to be unloaded for whatever reason.