Teleport is buggy

Vector3 is very buggy. I don't know if it is my code or just PocketMine. You can view my code below.

PHP:

$p->teleport($p->getLevel()->getSafeSpawn(new Vector3(mt_rand(0, 1*$this->getXFar()),
            mt_rand(0,1*$this->getYFar()), mt_rand(0,1*$this->getZFar())), $p->yaw, $p->pitch));

So far all you've given is code and say that Vector3 is buggy.
Explain how it's buggy.

When teleporting to a far location it freezes you and it kind of glitches. I think it could be the server memory?

Spoiler: server.properties

#Properties Config file
#Sun Nov 29 16:21:31 AKST 2015
motd=Minecraft: PE Server
server-port=19132
memory-limit=-1
white-list=off
announce-player-achievements=on
spawn-protection=16
max-players=20
allow-flight=off
spawn-animals=on
spawn-mobs=on
gamemode=0
force-gamemode=off
hardcore=off
pvp=on
difficulty=1
generator-settings=
level-name=world
level-seed=
level-type=DEFAULT
enable-query=on
enable-rcon=off
rcon.password=l4lrq9bc62
auto-save=on

Any messages in the console?

Not on teleport, but when I do '/op [name]' it freezes for a couple seconds and it says 'Can't keep up! Is server overloaded?' or something like that.

This was also seen by other coders, it happens on new Position too.