The Console log continually spams "root.tick" or "root.tick.textures" is "taking too long".
Further looking in my debug graph shows large activity dedicated to root.tick.textures with and without entities(Test with 100+ total Zombies, Creepers, Skeletons, Spiders, Slimes, and Zombie Pigmen)
Deeper In:
Profiling of Minecraft (using JProfiler) shows that classes
cl.class
cs.class
dh.class
are the most the intensive. Looking into these three shows that they call each other and are somehow related to possibly a block's texture, model, or block state model
Is this still an issue in the most recent versions (currently that is 1.10.2, or 16w43a) of Minecraft? If so, please update the affected versions and help us keeping this ticket updated from time to time. If you are the owner/reporter of this ticket, you can modify the affected version(s) yourself.