Paper/patches/server/0376-Add-Plugin-Tickets-to-API-Chunk-Methods.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

104 lines
6.0 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 9 Jun 2020 03:33:03 -0400
Subject: [PATCH] Add Plugin Tickets to API Chunk Methods
Like previous versions, plugins loading chunks kept them loaded until
they garbage collected to avoid constant spamming of chunk loads
This adds tickets to a few more places so that they can be unloaded.
Additionally, this drops their ticket level to BORDER so they wont be ticking
so they will just sit inactive instead.
Using .loadChunk to keep a chunk ticking was a horrible idea for upstream
when we have TWO methods that are able to do that already in the API.
Also reduce their collection count down to a maximum of 1 second. Barely
anyone knows what chunk-gc is in bukkit.yml as its less relevant now, and
since this wasn't spigot behavior, this is safe to mostly ignore (unless someone
wants it to collect even faster, they can restore that setting back to 1 instead of 20+)
Not adding it to .getType() though to keep behavior consistent with vanilla for performance reasons.
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index 89c4763b990ca9e801ee16c4a50e806740d061d9..0b288cc080869efed42a28be682f7b68f8691416 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -380,7 +380,7 @@ public final class CraftServer implements Server {
this.overrideSpawnLimits();
console.autosavePeriod = this.configuration.getInt("ticks-per.autosave");
this.warningState = WarningState.value(this.configuration.getString("settings.deprecated-verbose"));
- TicketType.PLUGIN.timeout = this.configuration.getInt("chunk-gc.period-in-ticks");
+ TicketType.PLUGIN.timeout = Math.min(20, this.configuration.getInt("chunk-gc.period-in-ticks")); // Paper - cap plugin loads to 1 second
this.minimumAPI = ApiVersion.getOrCreateVersion(this.configuration.getString("settings.minimum-api"));
this.loadIcon();
this.loadCompatibilities();
@@ -975,7 +975,7 @@ public final class CraftServer implements Server {
this.console.setMotd(config.motd);
this.overrideSpawnLimits();
this.warningState = WarningState.value(this.configuration.getString("settings.deprecated-verbose"));
- TicketType.PLUGIN.timeout = this.configuration.getInt("chunk-gc.period-in-ticks");
+ TicketType.PLUGIN.timeout = Math.min(20, configuration.getInt("chunk-gc.period-in-ticks")); // Paper - cap plugin loads to 1 second
this.minimumAPI = ApiVersion.getOrCreateVersion(this.configuration.getString("settings.minimum-api"));
this.printSaveWarning = false;
this.console.autosavePeriod = this.configuration.getInt("ticks-per.autosave");
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index a381688de78f5a78980b660f9765f839413a6c65..6e01013228798f9682624e912618500f0d4fa485 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -266,7 +266,13 @@ public class CraftWorld extends CraftRegionAccessor implements World {
@Override
public Chunk getChunkAt(int x, int z) {
- net.minecraft.world.level.chunk.LevelChunk chunk = (net.minecraft.world.level.chunk.LevelChunk) this.world.getChunk(x, z, ChunkStatus.FULL, true);
+ // Paper start - add ticket to hold chunk for a little while longer if plugin accesses it
+ net.minecraft.world.level.chunk.LevelChunk chunk = this.world.getChunkSource().getChunkAtIfLoadedImmediately(x, z);
+ if (chunk == null) {
+ this.addTicket(x, z);
+ chunk = this.world.getChunkSource().getChunk(x, z, true);
+ }
+ // Paper end
return new CraftChunk(chunk);
}
@@ -280,6 +286,12 @@ public class CraftWorld extends CraftRegionAccessor implements World {
return new CraftChunk(this.getHandle(), x, z);
}
+ // Paper start
+ private void addTicket(int x, int z) {
+ io.papermc.paper.util.MCUtil.MAIN_EXECUTOR.execute(() -> this.world.getChunkSource().addRegionTicket(TicketType.PLUGIN, new ChunkPos(x, z), 0, Unit.INSTANCE)); // Paper
+ }
+ // Paper end
+
@Override
public Chunk getChunkAt(Block block) {
Preconditions.checkArgument(block != null, "null block");
@@ -331,7 +343,7 @@ public class CraftWorld extends CraftRegionAccessor implements World {
public boolean unloadChunkRequest(int x, int z) {
org.spigotmc.AsyncCatcher.catchOp("chunk unload"); // Spigot
if (this.isChunkLoaded(x, z)) {
- this.world.getChunkSource().removeRegionTicket(TicketType.PLUGIN, new ChunkPos(x, z), 1, Unit.INSTANCE);
+ this.world.getChunkSource().removeRegionTicket(TicketType.PLUGIN, new ChunkPos(x, z), 0, Unit.INSTANCE); // Paper
}
return true;
@@ -441,7 +453,7 @@ public class CraftWorld extends CraftRegionAccessor implements World {
}
if (chunk instanceof net.minecraft.world.level.chunk.LevelChunk) {
- this.world.getChunkSource().addRegionTicket(TicketType.PLUGIN, new ChunkPos(x, z), 1, Unit.INSTANCE);
+ this.world.getChunkSource().addRegionTicket(TicketType.PLUGIN, new ChunkPos(x, z), 0, Unit.INSTANCE); // Paper
return true;
}
@@ -2241,6 +2253,7 @@ public class CraftWorld extends CraftRegionAccessor implements World {
ca.spottedleaf.moonrise.common.util.ChunkSystem.scheduleChunkLoad(this.getHandle(), x, z, gen, ChunkStatus.FULL, true, priority, (c) -> {
net.minecraft.server.MinecraftServer.getServer().scheduleOnMain(() -> {
net.minecraft.world.level.chunk.LevelChunk chunk = (net.minecraft.world.level.chunk.LevelChunk)c;
+ if (chunk != null) this.addTicket(x, z); // Paper
ret.complete(chunk == null ? null : new CraftChunk(chunk));
});
});