PaperMC/patches/server/0285-Optimize-Captured-BlockEntity-Lookup.patch
Bjarne Koll c5a10665b8
Remove wall-time / unused skip tick protection (#11412)
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.
2024-09-19 16:36:07 +02:00

30 lines
1.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 6 Apr 2019 10:16:48 -0400
Subject: [PATCH] Optimize Captured BlockEntity Lookup
upstream was doing a containsKey/get pattern, and always doing it at that.
that scenario is only even valid if were in the middle of a block place.
Optimize to check if the captured list even has values in it, and also to
just do a get call since the value can never be null.
diff --git a/src/main/java/net/minecraft/world/level/Level.java b/src/main/java/net/minecraft/world/level/Level.java
index 4c4449f7dee8695a362f83b9356e5754244fff18..60b04a16c6cb0a7109bda5c16e23c1d56ab7afad 100644
--- a/src/main/java/net/minecraft/world/level/Level.java
+++ b/src/main/java/net/minecraft/world/level/Level.java
@@ -912,9 +912,12 @@ public abstract class Level implements LevelAccessor, AutoCloseable {
@Nullable
public BlockEntity getBlockEntity(BlockPos blockposition, boolean validate) {
- if (this.capturedTileEntities.containsKey(blockposition)) {
- return this.capturedTileEntities.get(blockposition);
+ // Paper start - Perf: Optimize capturedTileEntities lookup
+ net.minecraft.world.level.block.entity.BlockEntity blockEntity;
+ if (!this.capturedTileEntities.isEmpty() && (blockEntity = this.capturedTileEntities.get(blockposition)) != null) {
+ return blockEntity;
}
+ // Paper end - Perf: Optimize capturedTileEntities lookup
// CraftBukkit end
return this.isOutsideBuildHeight(blockposition) ? null : (!this.isClientSide && Thread.currentThread() != this.thread ? null : this.getChunkAt(blockposition).getBlockEntity(blockposition, LevelChunk.EntityCreationType.IMMEDIATE));
}