Quote from VixenGold on 2019/02/01, 12:11

I only found out recently and then did some testing to confirm it.  Fast digging has a good chance to cause major lag.  Diamond pick eff 5 with beacon, and diamond shovel eff 3 or higher, without a beacon will make a lot of lag.  Until the issue can be fixed, please slow down a bit on the digging.  Thank you and Happy Building.