Upstream has released updates that appear to apply compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing.
Bukkit Changes:
d2834556 SPIGOT-4219: Event for PigZombies angering.
CraftBukkit Changes:
a9c796f1 SPIGOT-4184: Fix furnaces not matching Vanilla smelt or animations
195f071e SPIGOT-4219: Event for PigZombies angering.
5e3082c7 SPIGOT-4230: Improve legacy block types
CraftBukkit added synchronization to read and write methods. This adds
much more contention on this object for accessing region files, as
the entire read and write of NBT data is now a blocking operation.
This causes issues when something then simply needs to check if a chunk exists
on the main thread, causing a block...
However, this synchronization was unnecessary, because there is already
enough synchronization done to keep things safe
1) Obtaining a Region File: Those methods are still static synchronized.
Meaning we can safely obtain a Region File concurrently.
2) RegionFile data access: Methods reading and manipulating data from
a region file are also marked synchronized, ensuring that no 2 processes
are reading or writing data at the same time.
3) Checking a region file for chunkExists: getOffset is also synchronized
ensuring that even if a chunk is currently being written, it will be safe.
By removing these synchronizations, we reduce the locking to only
when data is being write or read.
GZIP compression and NBT Buffer creation will no longer be part of the
synchronized context, reducing lock times.
Ultimately: This brings us back to Vanilla, which has had no indication of region file loss.
Closes#1260
Aikar