From 2fbf2c556d7840198741959940696a14c7e3c26a Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sat, 18 Jun 2016 23:22:12 -0400
Subject: [PATCH] Delay Chunk Unloads based on Player Movement
When players are moving in the world, doing things such as building or exploring,
they will commonly go back and forth in a small area. This causes a ton of chunk load
and unload activity on the edge chunks of their view distance.
A simple back and forth movement in 6 blocks could spam a chunk to thrash a
loading and unload cycle over and over again.
This is very wasteful. This system introduces a delay of inactivity on a chunk
before it actually unloads, which is maintained separately from ChunkGC.
This allows servers with smaller worlds who do less long distance exploring to stop
wasting cpu cycles on saving/unloading/reloading chunks repeatedly.
This also makes the Chunk GC System useless, by auto scheduling unload as soon as
a spare chunk is added to the server thats outside of view distance.
diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
index bcc2ecaa3a..c70771614d 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -310,4 +310,18 @@ public class PaperWorldConfig {
preventTntFromMovingInWater = getBoolean("prevent-tnt-from-moving-in-water", false);
log("Prevent TNT from moving in water: " + preventTntFromMovingInWater);
}
+
+ public long delayChunkUnloadsBy;
+ private void delayChunkUnloadsBy() {
+ delayChunkUnloadsBy = PaperConfig.getSeconds(getString("delay-chunk-unloads-by", "10s"));
+ if (delayChunkUnloadsBy > 0) {
+ log("Delaying chunk unloads by " + delayChunkUnloadsBy + " seconds");
+ delayChunkUnloadsBy *= 1000;
+ }
+ }
+
+ public boolean skipEntityTickingInChunksScheduledForUnload = true;
+ private void skipEntityTickingInChunksScheduledForUnload() {
+ skipEntityTickingInChunksScheduledForUnload = getBoolean("skip-entity-ticking-in-chunks-scheduled-for-unload", skipEntityTickingInChunksScheduledForUnload);
+ }
}
diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
index c74176daa5..bdf922db50 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -40,6 +40,7 @@ public class Chunk implements IChunkAccess {
private boolean i;public boolean isLoaded() { return i; } // Paper - OBFHELPER
public final World world;
public final Map<HeightMap.Type, HeightMap> heightMap;
+ public Long scheduledForUnload; // Paper - delay chunk unloads
public final int locX;
public final int locZ;
private boolean l;
diff --git a/src/main/java/net/minecraft/server/ChunkMap.java b/src/main/java/net/minecraft/server/ChunkMap.java
index 8b3738c8f7..2021c0d02e 100644
--- a/src/main/java/net/minecraft/server/ChunkMap.java
+++ b/src/main/java/net/minecraft/server/ChunkMap.java
@@ -48,6 +48,15 @@ public class ChunkMap extends Long2ObjectOpenHashMap<Chunk> {
}
}
}
+ // Paper start - if this is a spare chunk (not part of any players view distance), go ahead and queue it for unload.
+ if (!((WorldServer)chunk.world).getPlayerChunkMap().isChunkInUse(chunk.locX, chunk.locZ)) {
+ if (chunk.world.paperConfig.delayChunkUnloadsBy > 0) {
+ chunk.scheduledForUnload = System.currentTimeMillis();
+ } else {
+ ((WorldServer) chunk.world).getChunkProvider().unload(chunk);
+ }
+ }
+ // Paper end
chunk.world.timings.syncChunkLoadPostTimer.stopTiming(); // Paper
// CraftBukkit end
diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index c54df45837..d0bf0f72da 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -307,6 +307,19 @@ public class ChunkProviderServer implements IChunkProvider {
}
activityAccountant.endActivity(); // Spigot
}
+ // Paper start - delayed chunk unloads
+ long now = System.currentTimeMillis();
+ long unloadAfter = world.paperConfig.delayChunkUnloadsBy;
+ if (unloadAfter > 0) {
+ //noinspection Convert2streamapi
+ for (Chunk chunk : chunks.values()) {
+ if (chunk.scheduledForUnload != null && now - chunk.scheduledForUnload > unloadAfter) {
+ chunk.scheduledForUnload = null;
+ unload(chunk);
+ }
+ }
+ }
+ // Paper end
this.chunkScheduler.a(booleansupplier);
}
diff --git a/src/main/java/net/minecraft/server/PlayerChunk.java b/src/main/java/net/minecraft/server/PlayerChunk.java
index e47aae2f8b..b9d90c4fb8 100644
--- a/src/main/java/net/minecraft/server/PlayerChunk.java
+++ b/src/main/java/net/minecraft/server/PlayerChunk.java
@@ -29,8 +29,23 @@ public class PlayerChunk {
chunkproviderserver.a(i, j);
this.chunk = chunkproviderserver.getChunkAt(i, j, true, false);
+ markChunkUsed(); // Paper - delay chunk unloads
}
+ // Paper start
+ private void markChunkUsed() {
+ if (chunk == null) {
+ return;
+ }
+ if (chunkHasPlayers) {
+ chunk.scheduledForUnload = null;
+ } else if (chunk.scheduledForUnload == null) {
+ chunk.scheduledForUnload = System.currentTimeMillis();
+ }
+ }
+ private boolean chunkHasPlayers = false;
+ // Paper end
+
public ChunkCoordIntPair a() {
return this.location;
}
@@ -41,6 +56,8 @@ public class PlayerChunk {
} else {
if (this.players.isEmpty()) {
this.i = this.playerChunkMap.getWorld().getTime();
+ chunkHasPlayers = true; // Paper - delay chunk unloads
+ markChunkUsed(); // Paper - delay chunk unloads
}
this.players.add(entityplayer);
@@ -59,6 +76,8 @@ public class PlayerChunk {
this.players.remove(entityplayer);
if (this.players.isEmpty()) {
+ chunkHasPlayers = false; // Paper - delay chunk unloads
+ markChunkUsed(); // Paper - delay chunk unloads
this.playerChunkMap.b(this);
}
@@ -70,6 +89,7 @@ public class PlayerChunk {
return true;
} else {
this.chunk = this.playerChunkMap.getWorld().getChunkProvider().getChunkAt(this.location.x, this.location.z, true, flag);
+ markChunkUsed(); // Paper - delay chunk unloads
return this.chunk != null;
}
}
diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
index 2064576501..ab4f3b7223 100644
--- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
+++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
@@ -452,7 +452,13 @@ public class PlayerChunkMap {
Chunk chunk = playerchunk.f();
if (chunk != null) {
- this.getWorld().getChunkProvider().unload(chunk);
+ // Paper start - delay chunk unloads
+ if (world.paperConfig.delayChunkUnloadsBy <= 0) {
+ this.getWorld().getChunkProvider().unload(chunk);
+ } else {
+ chunk.scheduledForUnload = System.currentTimeMillis();
+ }
+ // Paper end
}
}
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 32ee298648..dcff6c8d8a 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1293,7 +1293,13 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
if (!tileentity.x() && tileentity.hasWorld()) {
BlockPosition blockposition = tileentity.getPosition();
- if (this.isLoaded(blockposition) && this.K.a(blockposition)) {
+ // Paper start - Skip ticking in chunks scheduled for unload
+ net.minecraft.server.Chunk chunk = this.getChunkIfLoaded(blockposition);
+ boolean shouldTick = chunk != null;
+ if(this.paperConfig.skipEntityTickingInChunksScheduledForUnload)
+ shouldTick = shouldTick && chunk.scheduledForUnload == null;
+ if (shouldTick && this.K.a(blockposition)) {
+ // Paper end
try {
this.methodProfiler.a(() -> {
return String.valueOf(TileEntityTypes.a(tileentity.C()));
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index a8c7e7931e..f7883e7085 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -1772,7 +1772,7 @@ public class CraftWorld implements World {
ChunkProviderServer cps = world.getChunkProvider();
for (net.minecraft.server.Chunk chunk : cps.chunks.values()) {
// If in use, skip it
- if (isChunkInUse(chunk.locX, chunk.locZ)) {
+ if (isChunkInUse(chunk.locX, chunk.locZ) || chunk.scheduledForUnload != null) { // Paper - delayed chunk unloads
continue;
}
diff --git a/src/main/java/org/spigotmc/ActivationRange.java b/src/main/java/org/spigotmc/ActivationRange.java
index d08ef3fe10..081789a8fe 100644
--- a/src/main/java/org/spigotmc/ActivationRange.java
+++ b/src/main/java/org/spigotmc/ActivationRange.java
@@ -323,6 +323,11 @@ public class ActivationRange
{
isActive = false;
}
+ // Paper start - Skip ticking in chunks scheduled for unload
+ else if (entity.world.paperConfig.skipEntityTickingInChunksScheduledForUnload && (chunk == null || chunk.scheduledForUnload != null)) {
+ isActive = false;
+ }
+ // Paper end
return isActive;
}
}
--
2.21.0