Affects Version/s: Minecraft 15w49b, Minecraft 15w50a, Minecraft 15w51b, Minecraft 16w02a, Minecraft 16w03a, Minecraft 16w04a, Minecraft 16w05b
Fix Version/s: Minecraft 16w07a
Environment:see crash Report and Screenshots
Tested in new world and old world.
Problem happens earlier in old worlds.
I tested it with this Command:
Commandblock is in repeat-mode (activated via Redstoneblock).
In old worlds you need only 5 Commandblocks running this or any other Command like /testfor @e - in new worlds it needs up to 20 Commandblocks.
It needs vom 30s to 5 min to have those lags.
When the lags appear Mobs seem to be in slowmo.
commandBlockOutput is false