From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sun, 21 Mar 2021 16:25:42 -0700
Subject: [PATCH] Replace ticket level propagator
Mojang's propagator is slow, and this isn't surprising
given it's built on the same utilities the vanilla light engine
is built on. The simple propagator I wrote is approximately 4x
faster when simulating player movement. For a long time timing
reports have shown this function take up significant tick, (
approx 10% or more), and async sampling data shows the level
propagation alone takes up a significant amount. So this
should help with that. A big side effect is that mid-tick
will be more effective, since more time will be allocated
to actually processing chunk tasks vs the ticket level updates.
diff --git a/src/main/java/net/minecraft/server/level/DistanceManager.java b/src/main/java/net/minecraft/server/level/DistanceManager.java
index 06e4d3a02e0d1326b7029157856476db4ef3575e..f581a9f79b2357118d912a15344ff94df3b0c50e 100644
--- a/src/main/java/net/minecraft/server/level/DistanceManager.java
+++ b/src/main/java/net/minecraft/server/level/DistanceManager.java
@@ -38,6 +38,7 @@ import net.minecraft.world.level.chunk.ChunkStatus;
import net.minecraft.world.level.chunk.LevelChunk;
import org.slf4j.Logger;
+import it.unimi.dsi.fastutil.longs.Long2IntLinkedOpenHashMap; // Paper
public abstract class DistanceManager {
static final Logger LOGGER = LogUtils.getLogger();
@@ -48,7 +49,7 @@ public abstract class DistanceManager {
private static final int BLOCK_TICKING_LEVEL_THRESHOLD = 33;
final Long2ObjectMap<ObjectSet<ServerPlayer>> playersPerChunk = new Long2ObjectOpenHashMap();
public final Long2ObjectOpenHashMap<SortedArraySet<Ticket<?>>> tickets = new Long2ObjectOpenHashMap();
- private final DistanceManager.ChunkTicketTracker ticketTracker = new DistanceManager.ChunkTicketTracker();
+ //private final DistanceManager.ChunkTicketTracker ticketTracker = new DistanceManager.ChunkTicketTracker(); // Paper - replace ticket level propagator
public static final int MOB_SPAWN_RANGE = 8; // private final ChunkMapDistance.b f = new ChunkMapDistance.b(8); // Paper - no longer used
private final TickingTracker tickingTicketsTracker = new TickingTracker();
private final DistanceManager.PlayerTicketTracker playerTicketManager = new DistanceManager.PlayerTicketTracker(33);
@@ -83,6 +84,46 @@ public abstract class DistanceManager {
this.chunkMap = chunkMap; // Paper
}
+ // Paper start - replace ticket level propagator
+ protected final Long2IntLinkedOpenHashMap ticketLevelUpdates = new Long2IntLinkedOpenHashMap() {
+ @Override
+ protected void rehash(int newN) {
+ // no downsizing allowed
+ if (newN < this.n) {
+ return;
+ }
+ super.rehash(newN);
+ }
+ };
+ protected final io.papermc.paper.util.misc.Delayed8WayDistancePropagator2D ticketLevelPropagator = new io.papermc.paper.util.misc.Delayed8WayDistancePropagator2D(
+ (long coordinate, byte oldLevel, byte newLevel) -> {
+ DistanceManager.this.ticketLevelUpdates.putAndMoveToLast(coordinate, convertBetweenTicketLevels(newLevel));
+ }
+ );
+ // function for converting between ticket levels and propagator levels and vice versa
+ // the problem is the ticket level propagator will propagate from a set source down to zero, whereas mojang expects
+ // levels to propagate from a set value up to a maximum value. so we need to convert the levels we put into the propagator
+ // and the levels we get out of the propagator
+
+ // this maps so that GOLDEN_TICKET + 1 will be 0 in the propagator, GOLDEN_TICKET will be 1, and so on
+ // we need GOLDEN_TICKET+1 as 0 because anything >= GOLDEN_TICKET+1 should be unloaded
+ public static int convertBetweenTicketLevels(final int level) {
+ return ChunkMap.MAX_CHUNK_DISTANCE - level + 1;
+ }
+
+ protected final int getPropagatedTicketLevel(final long coordinate) {
+ return convertBetweenTicketLevels(this.ticketLevelPropagator.getLevel(coordinate));
+ }
+
+ protected final void updateTicketLevel(final long coordinate, final int ticketLevel) {
+ if (ticketLevel > ChunkMap.MAX_CHUNK_DISTANCE) {
+ this.ticketLevelPropagator.removeSource(coordinate);
+ } else {
+ this.ticketLevelPropagator.setSource(coordinate, convertBetweenTicketLevels(ticketLevel));
+ }
+ }
+ // Paper end - replace ticket level propagator
+
protected void purgeStaleTickets() {
++this.ticketTickCounter;
ObjectIterator objectiterator = this.tickets.long2ObjectEntrySet().fastIterator();
@@ -117,7 +158,7 @@ public abstract class DistanceManager {
}
if (flag) {
- this.ticketTracker.update(entry.getLongKey(), DistanceManager.getTicketLevelAt((SortedArraySet) entry.getValue()), false);
+ this.updateTicketLevel(entry.getLongKey(), getTicketLevelAt(entry.getValue())); // Paper - replace ticket level propagator
}
if (((SortedArraySet) entry.getValue()).isEmpty()) {
@@ -140,61 +181,94 @@ public abstract class DistanceManager {
@Nullable
protected abstract ChunkHolder updateChunkScheduling(long pos, int level, @Nullable ChunkHolder holder, int k);
+ protected long ticketLevelUpdateCount; // Paper - replace ticket level propagator
public boolean runAllUpdates(ChunkMap chunkStorage) {
//this.f.a(); // Paper - no longer used
this.tickingTicketsTracker.runAllUpdates();
org.spigotmc.AsyncCatcher.catchOp("DistanceManagerTick"); // Paper
this.playerTicketManager.runAllUpdates();
- int i = Integer.MAX_VALUE - this.ticketTracker.runDistanceUpdates(Integer.MAX_VALUE);
- boolean flag = i != 0;
+ boolean flag = this.ticketLevelPropagator.propagateUpdates(); // Paper - replace ticket level propagator
if (flag) {
;
}
- // Paper start
- if (!this.pendingChunkUpdates.isEmpty()) {
- this.pollingPendingChunkUpdates = true; try { // Paper - Chunk priority
- while(!this.pendingChunkUpdates.isEmpty()) {
- ChunkHolder remove = this.pendingChunkUpdates.remove();
- remove.isUpdateQueued = false;
- remove.updateFutures(chunkStorage, this.mainThreadExecutor);
- }
- } finally { this.pollingPendingChunkUpdates = false; } // Paper - Chunk priority
- // Paper end
- return true;
- } else {
- if (!this.ticketsToRelease.isEmpty()) {
- LongIterator longiterator = this.ticketsToRelease.iterator();
+ // Paper start - replace level propagator
+ ticket_update_loop:
+ while (!this.ticketLevelUpdates.isEmpty()) {
+ flag = true;
- while (longiterator.hasNext()) {
- long j = longiterator.nextLong();
+ boolean oldPolling = this.pollingPendingChunkUpdates;
+ this.pollingPendingChunkUpdates = true;
+ try {
+ for (java.util.Iterator<Long2IntMap.Entry> iterator = this.ticketLevelUpdates.long2IntEntrySet().fastIterator(); iterator.hasNext();) {
+ Long2IntMap.Entry entry = iterator.next();
+ long key = entry.getLongKey();
+ int newLevel = entry.getIntValue();
+ ChunkHolder chunk = this.getChunk(key);
+
+ if (chunk == null && newLevel > ChunkMap.MAX_CHUNK_DISTANCE) {
+ // not loaded and it shouldn't be loaded!
+ continue;
+ }
- if (this.getTickets(j).stream().anyMatch((ticket) -> {
- return ticket.getType() == TicketType.PLAYER;
- })) {
- ChunkHolder playerchunk = chunkStorage.getUpdatingChunkIfPresent(j);
+ int currentLevel = chunk == null ? ChunkMap.MAX_CHUNK_DISTANCE + 1 : chunk.getTicketLevel();
- if (playerchunk == null) {
- throw new IllegalStateException();
+ if (currentLevel == newLevel) {
+ // nothing to do
+ continue;
+ }
+
+ this.updateChunkScheduling(key, newLevel, chunk, currentLevel);
+ }
+
+ long recursiveCheck = ++this.ticketLevelUpdateCount;
+ while (!this.ticketLevelUpdates.isEmpty()) {
+ long key = this.ticketLevelUpdates.firstLongKey();
+ int newLevel = this.ticketLevelUpdates.removeFirstInt();
+ ChunkHolder chunk = this.getChunk(key);
+
+ if (chunk == null) {
+ if (newLevel <= ChunkMap.MAX_CHUNK_DISTANCE) {
+ throw new IllegalStateException("Expected chunk holder to be created");
}
+ // not loaded and it shouldn't be loaded!
+ continue;
+ }
- CompletableFuture<Either<LevelChunk, ChunkHolder.ChunkLoadingFailure>> completablefuture = playerchunk.getEntityTickingChunkFuture();
+ int currentLevel = chunk.oldTicketLevel;
- completablefuture.thenAccept((either) -> {
- this.mainThreadExecutor.execute(() -> {
- this.ticketThrottlerReleaser.tell(ChunkTaskPriorityQueueSorter.release(() -> {
- }, j, false));
- });
- });
+ if (currentLevel == newLevel) {
+ // nothing to do
+ continue;
+ }
+
+ chunk.updateFutures(chunkStorage, this.mainThreadExecutor);
+ if (recursiveCheck != this.ticketLevelUpdateCount) {
+ // back to the start, we must create player chunks and update the ticket level fields before
+ // processing the actual level updates
+ continue ticket_update_loop;
}
}
- this.ticketsToRelease.clear();
- }
+ for (;;) {
+ if (recursiveCheck != this.ticketLevelUpdateCount) {
+ continue ticket_update_loop;
+ }
+ ChunkHolder pendingUpdate = this.pendingChunkUpdates.poll();
+ if (pendingUpdate == null) {
+ break;
+ }
- return flag;
+ pendingUpdate.updateFutures(chunkStorage, this.mainThreadExecutor);
+ }
+ } finally {
+ this.pollingPendingChunkUpdates = oldPolling;
+ }
}
+
+ return flag;
+ // Paper end - replace level propagator
}
boolean pollingPendingChunkUpdates = false; // Paper - Chunk priority
@@ -206,7 +280,7 @@ public abstract class DistanceManager {
ticket1.setCreatedTick(this.ticketTickCounter);
if (ticket.getTicketLevel() < j) {
- this.ticketTracker.update(i, ticket.getTicketLevel(), true);
+ this.updateTicketLevel(i, ticket.getTicketLevel()); // Paper - replace ticket level propagator
}
return ticket == ticket1; // CraftBukkit
@@ -250,7 +324,7 @@ public abstract class DistanceManager {
// Paper start - Chunk priority
int newLevel = getTicketLevelAt(arraysetsorted);
if (newLevel > oldLevel) {
- this.ticketTracker.update(i, newLevel, false);
+ this.updateTicketLevel(i, newLevel); // Paper // Paper - replace ticket level propagator
}
// Paper end
return removed; // CraftBukkit
@@ -564,7 +638,7 @@ public abstract class DistanceManager {
}
if (flag) {
- this.ticketTracker.update(entry.getLongKey(), DistanceManager.getTicketLevelAt((SortedArraySet) entry.getValue()), false);
+ this.updateTicketLevel(entry.getLongKey(), DistanceManager.getTicketLevelAt((SortedArraySet) entry.getValue())); // Paper - replace ticket level propagator
}
if (((SortedArraySet) entry.getValue()).isEmpty()) {
@@ -587,7 +661,7 @@ public abstract class DistanceManager {
SortedArraySet<Ticket<?>> tickets = entry.getValue();
if (tickets.remove(target)) {
// copied from removeTicket
- this.ticketTracker.update(entry.getLongKey(), DistanceManager.getTicketLevelAt(tickets), false);
+ this.updateTicketLevel(entry.getLongKey(), getTicketLevelAt(tickets)); // Paper - replace ticket level propagator
// can't use entry after it's removed
if (tickets.isEmpty()) {