Sometimes it shows a lot of corpses and the FPS is very low!
Replies

IIRC, this bug can be caused by empty Ammo Bag on client (useable amount is 0), but that Ammo Bag still has something on host (usually the amount is 0.00001).
If that happens, it blocks dead bodies from despawning.
The only fix for that is to host has to use that bugged Ammo Bag. This will delete it and dead bodies will despawn again.

Not sure if you need to be host, but maybe Goonmod Corpse Remover Standalone can help you?
idk if this helps but in the settings on the game you can reduce the corpse limit
Settings ---> Video --- > Advanced