Spigot still maintains some partial implementation of "tick skipping", a
practice in which the MinecraftServer.currentTick field is updated not
by an increment of one per actual tick, but instead set to
System.currentTimeMillis() / 50. This behaviour means that the tracked
tick may "skip" a tick value in case a previous tick took more than the
expected 50ms.
To compensate for this in important paths, spigot/craftbukkit
implements "wall-time". Instead of incrementing/decrementing ticks on
block entities/entities by one for each call to their tick() method,
they instead increment/decrement important values, like
an ItemEntity's age or pickupDelay, by the difference of
`currentTick - lastTick`, where `lastTick` is the value of
`currentTick` during the last tick() call.
These "fixes" however do not play nicely with minecraft's simulation
distance as entities/block entities implementing the above behaviour
would "catch up" their values when moving from a non-ticking chunk to a
ticking one as their `lastTick` value remains stuck on the last tick in
a ticking chunk and hence lead to a large "catch up" once ticked again.
Paper completely removes the "tick skipping" behaviour (See patch
"Further-improve-server-tick-loop"), making the above precautions
completely unnecessary, which also rids paper of the previous described
incompatibility with non-ticking chunks.
Co-authored-by: Shane Freeder <theboyetronic@gmail.com>
Also, restores un/loading worlds mid tick. This will not be officially supported API contract that such a routine is safe, and these restrictions may be restored in the future.
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing
CraftBukkit Changes:
ead719a65 SPIGOT-7136: Cancelling PlayerInteractEntityEvent with the Allay desyncs
8468e167e SPIGOT-7137: StructureGrowEvent isFromBonemeal and getPlayer have incorrect values
d45057c59 SPIGOT-7089: Crash when command blocks attempt to load worlds
Spigot Changes:
450dcaa8 Rebuild patches
