I'm not 100% sure on this but CB++ gives the server a certain amount of RAM depending on players in the world. So if your server has a maximum of 2gb (which mine does), and there is only 2 players online it will allocate enough RAM for those 2 players only. How many players do you have online at the moment? I highly suggest you look at the newly created bukkit.yml config and edit the settings, see below.
Pay attention to the mob spawn limits and growth settings. Also change the view distance in your server.cfg file to something less than 10, I have mine on 6. Which is about 300 odd chunks less per person loaded which can make a massive difference to a servers performance.
settings:
allow-end: false
warn-on-overload: false
kick-on-speedhack: true
spawn-radius: 16
permissions-file: permissions.yml
update-folder: update
ping-packet-limit: 100
use-exact-login-location: false
plugin-profiling: false
connection-throttle: 4000
query-plugins: true
restart-script-location: start.bat
timeout-time: 180
restart-on-crash: false
filter-unsafe-ips: true
whitelist-message: You are not white-listed on this server!
deprecated-verbose: default
world-settings:
default:
growth-chunks-per-tick: 2000
mob-spawn-range: 5
monsters-per-chunk: 40
land-creatures-per-chunk: 5
water-creatures-per-chunk: 5
item-merge-radius: 3.5
random-light-updates: false
aggregate-chunkticks: 4
chunky-freeze-temperature: true
wheat-growth-modifier: 100
cactus-growth-modifier: 100
melon-growth-modifier: 100
pumpkin-growth-modifier: 100
sugar-growth-modifier: 100
tree-growth-modifier: 100
mushroom-growth-modifier: 100
world:
growth-chunks-per-tick: 30
world_nether:
growth-chunks-per-tick: 0
random-light-updates: true
water-creatures-per-chunk: 0
spawn-limits:
monsters: 70
animals: 15
water-animals: 5
ticks-per:
animal-spawns: 400
monster-spawns: 1
auto-updater:
enabled: true
on-broken:
- warn-console
- warn-ops
on-update:
- warn-console
- warn-ops
preferred-channel: rb
host: dl.bukkit.org
suggest-channels: true
database:
username: bukkit
isolation: SERIALIZABLE
driver: org.sqlite.JDBC
password: walrus
url: jdbc:sqlite:{DIR}{NAME}.db
storm-settings:
strong-electrical-storm:
chance: 5
lightning-delay: 10
lightning-random-delay: 20
electrical-storm:
chance: 15
lightning-delay: 40
lightning-random-delay: 150
strong-thunderstorm:
chance: 30
lightning-delay: 60
lightning-random-delay: 250
thunderstorm:
chance: 50
lightning-delay: 100
lightning-random-delay: 500
weak-thunderstorm:
chance: 75
lightning-delay: 300
lightning-random-delay: 1000
rainstorm:
chance: 100
lightning-delay: 500
lightning-random-delay: 2000