@Vil, the Ps stone do not protect any unlocked chests before the 1.9 update, I am pretty sure this is a bug. My iron farm has been running for 2 months after it was built and all along there was a ps stone under the unlocked chests in a room. Players were able to access it, and now they cannot after the 1.9 update. There are much more situations like this, plz fix.
Furthermore, the entity lag is only reduced but not gone, my pigmen at my farm is still falling at 3 blocks a second, over twice as slow. My guardians and iron golems are taking lava damage at half the rate, and falling half as slow. Basically this applies to any mob that is not in the end. Also, no one can shoot arrows at full speed, and minecrarts travel sow.
Furthermore, the entity lag is only reduced but not gone, my pigmen at my farm is still falling at 3 blocks a second, over twice as slow. My guardians and iron golems are taking lava damage at half the rate, and falling half as slow. Basically this applies to any mob that is not in the end. Also, no one can shoot arrows at full speed, and minecrarts travel sow.