Minecraft Solution to the Mob Grinder Bug 1.7/1.8
Why Arqade Stack Exchange recommends it
Arqade (Gaming Stack Exchange) answerers link it when explaining why a mob trap or grinder stops spawning mobs, since it documents the cause and a working fix.
Recommended by 1 people across 1 different months, 2011 to 2012.
What it is
A 2011 Minecraft video by Erik Nohr showing the fix for the mob grinder bug, where spawning dries up over time. It confirms a theory that mobs spawn or wander into an outer border zone of loaded chunks, never despawn, and fill the mob cap. He demonstrates the fix with chunk maps and a grinder that keeps producing drops overnight.
What people said
Recommends Fnord Prefect · 2012-01 · Arqade Stack Exchange · on “What's wrong with my mob trap?”
Mobs naturally despawn after a while, so the mobs in the caves in the active chunks aren't really the problem. Even after you carefully find and light all the caves in all the active chunks around where you're standing when you use the mob farm, there is a 20m "border zone" around the outside of the active chunks in which mobs can end up (either they wander there from active chunks or a group of mobs spawn on the edge of an active chunk and some of the group thus spawns in the inactive area.) These mobs that are not in active chunks are immune to despawn, and so eventually reach mob cap and hurt your output. Details: (I suggest skipping to 8 or 11 minutes if you've ever felt "tl;dw" about vi
Cites Richard Benson · 2011-10 · Arqade Stack Exchange · on “What effect does framerate have on mob spawning?”
I know this is an old question, but it came up in a Google. It has recently been theorised (and to a certain extent proved) that there is a bug related to mobs spawning on the edge of the loaded chunk area, wandering out and still using up the mob limit. Further analysis and experimentation is available in this video [this video] .
Cites Jonathan · 2012-12 · Arqade Stack Exchange · on “Why doesn't my mob grinder spawn mobs?”
@everyone, I researched my problem and saw this video which had the most promise: " [this video] " Essentially the mobs thats spawn near the ~240x240 block radius move out of the blocks loaded by the user and cannot despawn anymore. I'm thinking If I increase the memory useage to 2+GB It will despawn them. Problem is I need to wait for my RMA'd memory to return, it will anyday now to test it out. Thanks all for the answers, it is much appreciated!