PaperMC/Spigot-Server-Patches/0366-incremental-chunk-saving.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sun, 9 Jun 2019 03:53:22 +0100
Subject: [PATCH] incremental chunk saving


diff --git a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
index 44811683cfe47adbdce6c8bd627bdbeb13ce114c..e7c73a4ddbb42aa52112147a60c8a761bfd3d07b 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -439,4 +439,19 @@ public class PaperWorldConfig {
         keepLoadedRange = (short) (getInt("keep-spawn-loaded-range", Math.min(spigotConfig.viewDistance, 10)) * 16);
         log( "Keep Spawn Loaded Range: " + (keepLoadedRange/16));
     }
+
+    public int autoSavePeriod = -1;
+    private void autoSavePeriod() {
+        autoSavePeriod = getInt("auto-save-interval", -1);
+        if (autoSavePeriod > 0) {
+            log("Auto Save Interval: " +autoSavePeriod + " (" + (autoSavePeriod / 20) + "s)");
+        } else if (autoSavePeriod < 0) {
+            autoSavePeriod = net.minecraft.server.MinecraftServer.getServer().autosavePeriod;
+        }
+    }
+
+    public int maxAutoSaveChunksPerTick = 24;
+    private void maxAutoSaveChunksPerTick() {
+        maxAutoSaveChunksPerTick = getInt("max-auto-save-chunks-per-tick", 24);
+    }
 }
diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
index 8e3244fc5c6e5fff22857637b4ab5944d6b1e165..62758052546fac25fc90a9d26e5081d92eeba8b5 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -43,7 +43,7 @@ public class Chunk implements IChunkAccess {
     private TickList<Block> o;
     private TickList<FluidType> p;
     private boolean q;
-    private long lastSaved;
+    public long lastSaved; // Paper
     private volatile boolean s;
     private long inhabitedTime;
     @Nullable
diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
index 3bfd225db6945cb431238a9a980fb6d10f831f61..b49420bdbdd00148fc5f9a21d3f4953457b2cdc6 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -536,6 +536,15 @@ public class ChunkProviderServer extends IChunkProvider {
         } // Paper - Timings
     }
 
+    // Paper start - duplicate save, but call incremental
+    public void saveIncrementally() {
+        this.tickDistanceManager();
+        try (co.aikar.timings.Timing timed = world.timings.chunkSaveData.startTiming()) { // Paper - Timings
+            this.playerChunkMap.saveIncrementally();
+        } // Paper - Timings
+    }
+    // Paper end
+
     @Override
     public void close() throws IOException {
         // CraftBukkit start
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index e6e4e8c07b0283bdf45c8dac3cc47336a7430ca3..122485e7351791e54e1d2ac8a71e3623a8d4cb29 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -152,6 +152,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
     public static int currentTick = 0; // Paper - Further improve tick loop
     public java.util.Queue<Runnable> processQueue = new java.util.concurrent.ConcurrentLinkedQueue<Runnable>();
     public int autosavePeriod;
+    public boolean serverAutoSave = false; // Paper
     public CommandDispatcher vanillaCommandDispatcher;
     private boolean forceTicks;
     // CraftBukkit end
@@ -1141,14 +1142,24 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
             this.serverPing.b().a(agameprofile);
         }
 
-        if (autosavePeriod > 0 && this.ticks % autosavePeriod == 0) { // CraftBukkit
-            MinecraftServer.LOGGER.debug("Autosave started");
+        //if (autosavePeriod > 0 && this.ticks % autosavePeriod == 0) { // CraftBukkit // Paper - move down
+            //MinecraftServer.LOGGER.debug("Autosave started"); // Paper
+            serverAutoSave = (autosavePeriod > 0 && this.ticks % autosavePeriod == 0); // Paper
             this.methodProfiler.enter("save");
+            if (autosavePeriod > 0 && this.ticks % autosavePeriod == 0) { // Paper
             this.playerList.savePlayers();
-            this.saveChunks(true, false, false);
+            }// Paper
+            // Paper start
+            for (WorldServer world : getWorlds()) {
+                if (world.paperConfig.autoSavePeriod > 0) {
+                    world.saveIncrementally(serverAutoSave);
+                }
+            }
+            // Paper end
+
             this.methodProfiler.exit();
-            MinecraftServer.LOGGER.debug("Autosave finished");
-        }
+            //MinecraftServer.LOGGER.debug("Autosave finished"); // Paper
+        //} // Paper
 
         this.methodProfiler.enter("snooper");
         if (((DedicatedServer) this).getDedicatedServerProperties().snooperEnabled && !this.snooper.d() && this.ticks > 100) { // Spigot
diff --git a/src/main/java/net/minecraft/server/PlayerChunk.java b/src/main/java/net/minecraft/server/PlayerChunk.java
index 3f125a57f43ea1678bd891ab7c1e6b892de55542..f558fa255933cbe9f15a6fa8e2dcd456380e5620 100644
--- a/src/main/java/net/minecraft/server/PlayerChunk.java
+++ b/src/main/java/net/minecraft/server/PlayerChunk.java
@@ -42,6 +42,9 @@ public class PlayerChunk {
 
     private final PlayerChunkMap chunkMap; // Paper
 
+    long lastAutoSaveTime; // Paper - incremental autosave
+    long inactiveTimeStart; // Paper - incremental autosave
+
     public PlayerChunk(ChunkCoordIntPair chunkcoordintpair, int i, LightEngine lightengine, PlayerChunk.c playerchunk_c, PlayerChunk.d playerchunk_d) {
         this.statusFutures = new AtomicReferenceArray(PlayerChunk.CHUNK_STATUSES.size());
         this.fullChunkFuture = PlayerChunk.UNLOADED_CHUNK_FUTURE;
@@ -393,7 +396,19 @@ public class PlayerChunk {
         boolean flag2 = playerchunk_state.isAtLeast(PlayerChunk.State.BORDER);
         boolean flag3 = playerchunk_state1.isAtLeast(PlayerChunk.State.BORDER);
 
+        boolean prevHasBeenLoaded = this.hasBeenLoaded; // Paper
         this.hasBeenLoaded |= flag3;
+        // Paper start - incremental autosave
+        if (this.hasBeenLoaded & !prevHasBeenLoaded) {
+            long timeSinceAutoSave = this.inactiveTimeStart - this.lastAutoSaveTime;
+            if (timeSinceAutoSave < 0) {
+                // safest bet is to assume autosave is needed here
+                timeSinceAutoSave = this.chunkMap.world.paperConfig.autoSavePeriod;
+            }
+            this.lastAutoSaveTime = this.chunkMap.world.getTime() - timeSinceAutoSave;
+            this.chunkMap.autoSaveQueue.add(this);
+        }
+        // Paper end
         if (!flag2 && flag3) {
             // Paper start - cache ticking ready status
             int expectCreateCount = ++this.fullChunkCreateCount;
@@ -513,8 +528,32 @@ public class PlayerChunk {
     }
 
     public void m() {
+        boolean prev = this.hasBeenLoaded; // Paper
+        this.hasBeenLoaded = getChunkState(this.ticketLevel).isAtLeast(PlayerChunk.State.BORDER);
+        // Paper start - incremental autosave
+        if (prev != this.hasBeenLoaded) {
+            if (this.hasBeenLoaded) {
+                long timeSinceAutoSave = this.inactiveTimeStart - this.lastAutoSaveTime;
+                if (timeSinceAutoSave < 0) {
+                    // safest bet is to assume autosave is needed here
+                    timeSinceAutoSave = this.chunkMap.world.paperConfig.autoSavePeriod;
+                }
+                this.lastAutoSaveTime = this.chunkMap.world.getTime() - timeSinceAutoSave;
+                this.chunkMap.autoSaveQueue.add(this);
+            } else {
+                this.inactiveTimeStart = this.chunkMap.world.getTime();
+                this.chunkMap.autoSaveQueue.remove(this);
+            }
+        }
+        // Paper end
+    }
+
+    // Paper start - incremental autosave
+    public boolean setHasBeenLoaded() {
         this.hasBeenLoaded = getChunkState(this.ticketLevel).isAtLeast(PlayerChunk.State.BORDER);
+        return this.hasBeenLoaded;
     }
+    // Paper end
 
     public void a(ProtoChunkExtension protochunkextension) {
         for (int i = 0; i < this.statusFutures.length(); ++i) {
diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
index d8bedba819fa9ee0a4d3bdfbf0b010da7144dd68..c4ed4d58f7b344626acb13baeb14288970a7bb90 100644
--- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
+++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
@@ -47,6 +47,7 @@ import java.util.function.Supplier;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 import javax.annotation.Nullable;
+import it.unimi.dsi.fastutil.objects.ObjectRBTreeSet; // Paper
 import org.apache.commons.lang3.mutable.MutableBoolean;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -333,6 +334,64 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
 
     }
 
+    // Paper start - incremental autosave
+    final ObjectRBTreeSet<PlayerChunk> autoSaveQueue = new ObjectRBTreeSet<>((playerchunk1, playerchunk2) -> {
+        int timeCompare =  Long.compare(playerchunk1.lastAutoSaveTime, playerchunk2.lastAutoSaveTime);
+        if (timeCompare != 0) {
+            return timeCompare;
+        }
+
+        return Long.compare(MCUtil.getCoordinateKey(playerchunk1.location), MCUtil.getCoordinateKey(playerchunk2.location));
+    });
+
+    protected void saveIncrementally() {
+        int savedThisTick = 0;
+        // optimized since we search far less chunks to hit ones that need to be saved
+        List<PlayerChunk> reschedule = new java.util.ArrayList<>(this.world.paperConfig.maxAutoSaveChunksPerTick);
+        long currentTick = this.world.getTime();
+        long maxSaveTime = currentTick - this.world.paperConfig.autoSavePeriod;
+
+        for (Iterator<PlayerChunk> iterator = this.autoSaveQueue.iterator(); iterator.hasNext();) {
+            PlayerChunk playerchunk = iterator.next();
+            if (playerchunk.lastAutoSaveTime > maxSaveTime) {
+                break;
+            }
+
+            iterator.remove();
+
+            IChunkAccess ichunkaccess = playerchunk.getChunkSave().getNow(null);
+            if (ichunkaccess instanceof Chunk) {
+                boolean shouldSave = ((Chunk)ichunkaccess).lastSaved <= maxSaveTime;
+
+                if (shouldSave && this.saveChunk(ichunkaccess)) {
+                    ++savedThisTick;
+
+                    if (!playerchunk.setHasBeenLoaded()) {
+                        // do not fall through to reschedule logic
+                        playerchunk.inactiveTimeStart = currentTick;
+                        if (savedThisTick >= this.world.paperConfig.maxAutoSaveChunksPerTick) {
+                            break;
+                        }
+                        continue;
+                    }
+                }
+            }
+
+            reschedule.add(playerchunk);
+
+            if (savedThisTick >= this.world.paperConfig.maxAutoSaveChunksPerTick) {
+                break;
+            }
+        }
+
+        for (int i = 0, len = reschedule.size(); i < len; ++i) {
+            PlayerChunk playerchunk = reschedule.get(i);
+            playerchunk.lastAutoSaveTime = this.world.getTime();
+            this.autoSaveQueue.add(playerchunk);
+        }
+    }
+    // Paper end
+
     protected void save(boolean flag) {
         if (flag) {
             List<PlayerChunk> list = (List) this.visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).peek(PlayerChunk::m).collect(Collectors.toList());
@@ -443,6 +502,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
 
                         this.world.unloadChunk(chunk);
                     }
+                    this.autoSaveQueue.remove(playerchunk); // Paper
 
                     this.lightEngine.a(ichunkaccess.getPos());
                     this.lightEngine.queueUpdate();
@@ -635,6 +695,8 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
                     playerchunk.a(new ProtoChunkExtension(chunk));
                 }
 
+                chunk.setLastSaved(this.world.getTime() - 1); // Paper - avoid autosaving newly generated/loaded chunks
+
                 chunk.a(() -> {
                     return PlayerChunk.getChunkState(playerchunk.getTicketLevel());
                 });
diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index da6d9495c869150ce83dfb284c5977d7f122e71b..c679a3838a5f4c180fbc258d59cf202a6bd91a16 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -768,11 +768,43 @@ public class WorldServer extends World implements GeneratorAccessSeed {
         return !this.server.a(this, blockposition, entityhuman) && this.getWorldBorder().a(blockposition);
     }
 
+    // Paper start - derived from below
+    public void saveIncrementally(boolean doFull) {
+        ChunkProviderServer chunkproviderserver = this.getChunkProvider();
+
+        if (doFull) {
+            org.bukkit.Bukkit.getPluginManager().callEvent(new org.bukkit.event.world.WorldSaveEvent(getWorld()));
+        }
+
+        try (co.aikar.timings.Timing ignored = timings.worldSave.startTiming()) {
+            if (doFull) {
+                this.saveData();
+            }
+
+            timings.worldSaveChunks.startTiming(); // Paper
+            if (!this.isSavingDisabled()) chunkproviderserver.saveIncrementally();
+            timings.worldSaveChunks.stopTiming(); // Paper
+
+
+            // Copied from save()
+            // CraftBukkit start - moved from MinecraftServer.saveChunks
+            if (doFull) { // Paper
+                WorldServer worldserver1 = this;
+
+                worldDataServer.a(worldserver1.getWorldBorder().t());
+                worldDataServer.setCustomBossEvents(this.server.getBossBattleCustomData().save());
+                convertable.a(this.server.f, this.worldDataServer, this.server.getPlayerList().save());
+            }
+            // CraftBukkit end
+        }
+    }
+    // Paper end
+
     public void save(@Nullable IProgressUpdate iprogressupdate, boolean flag, boolean flag1) {
         ChunkProviderServer chunkproviderserver = this.getChunkProvider();
 
         if (!flag1) {
-            org.bukkit.Bukkit.getPluginManager().callEvent(new org.bukkit.event.world.WorldSaveEvent(getWorld())); // CraftBukkit
+            if (flag) org.bukkit.Bukkit.getPluginManager().callEvent(new org.bukkit.event.world.WorldSaveEvent(getWorld())); // CraftBukkit // Paper
             try (co.aikar.timings.Timing ignored = timings.worldSave.startTiming()) { // Paper
             if (iprogressupdate != null) {
                 iprogressupdate.a(new ChatMessage("menu.savingLevel"));
@@ -798,6 +830,7 @@ public class WorldServer extends World implements GeneratorAccessSeed {
         // CraftBukkit end
     }
 
+    private void saveData() { this.ai(); } // Paper - OBFHELPER
     private void ai() {
         if (this.dragonBattle != null) {
             this.worldDataServer.a(this.dragonBattle.a()); // CraftBukkit