Clumps
Supported versions of minecraft

Clumps groups XP orbs together into a single entity and sends it to the nearest player to reduce lag. On top of this, it also makes the player immediately collect the orbs once they touch the player, so you are not stuck with a bunch of orbs in your face. With this add-on, you don't have to worry about XP orbs and XP farms causing lag in your world/server.