jargon.artrocity.com
New Hacker's Dictionary the Jargon File v 4.4.6
A lowest-priority task that waits around until everything else has ‘had its fill’ of machine resources. Only when the machine would otherwise be idle is the task allowed to `‘suck up the slop’. Also called a hungry puppy or bottom feeder. One common variety of slopsucker hunts for large prime numbers. Compare background.