In the particle renderer there's no frustrum culling check when rendering particles. If frustrum culling was added it would help performance in places where there are a lot of particles.

For people who don't know what frustrum culling is, it's basically makes it so objects don't render if they are outside of your view. Almost all entites and all tile entities in Minecraft already use frustrum culling so it would be a simple thing to add to particles too.

Technical information for developer:
Just pass the Frustrum object to the particle renderer method and add a basic if statement that does a check using the particle entity's bounding box. You might also have to update the size on some particles so they render properly. But if you can't change the size because of collision detection it might be handy if you add a render bounding box to entities.