Are there any portal other plugins that don't take up a lot of CPU?

I'm having an issue with my CPU usage on my server. I'm using multiverse portals and core and they work fine, its just if 2 or more players decide to go through a portal everyone gets a lag spike and the TPS go's either way up or way down. >.< My questions are could someone be ddosing us? What things would be affected in a ddos attack? Can anyone recommend another portals plugin that doesn't use a lot of CPU? Are there any plugins that cut down on CPU usage?
Thank you and if you just know one of these questions please commend below.
http://dev.bukkit.org/server-mods/multiverse-portals/

~BlockTheEnd

Also, does Multiversework with Bungee-Cord or is that a planed feature?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

I highly doubt Multiverse lags everybody out just because 2 players use a portal. It's just a teleport, basically. Sounds more like you have a very low bandwidth/io issues. And how could "TPS go either way up or way down"?

Certainly not ddos.