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 071e5e7f729d6c3ffb70506e7ef32eebee1e9118..48676152152faf7a7b9524ac37d8b4a8c32c4e2c 100644
--- a/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperWorldConfig.java
@@ -487,4 +487,19 @@ 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 165cb994e84bbcbdeb5ec14b561433257fd0df28..af0d6aff4de78e81fd3feb16719efdccc05ccb90 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -42,7 +42,7 @@ 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 e6d08756f76360b29b29f18305e5ec84d09f2d54..6713b7667ae4fe3f1f555a71321832b4a9492162 100644
--- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
+++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
@@ -515,6 +515,15 @@ 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 8b499c815c77bf5b356d4216ba6cbf2a329c9aca..cfed5f51431ec5aecb538a321327bfb6e8a0bd88 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -168,6 +168,7 @@ 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 File bukkitDataPackFolder;
     public CommandDispatcher vanillaCommandDispatcher;
     private boolean forceTicks;
@@ -1116,14 +1117,28 @@ 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) {
+                    try {
+                        world.saveIncrementally(serverAutoSave);
+                    } catch (ExceptionWorldConflict exceptionWorldConflict) {
+                        MinecraftServer.LOGGER.warn(exceptionWorldConflict.getMessage());
+                    }
+                }
+            }
+            // 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 a640cb3845a853780b8cc2dbfc6e9be3728817e7..3d255b19647fb37f53a420c907bc634181580c18 100644
--- a/src/main/java/net/minecraft/server/PlayerChunk.java
+++ b/src/main/java/net/minecraft/server/PlayerChunk.java
@@ -40,6 +40,9 @@ 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;
@@ -385,7 +388,19 @@ 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;
@@ -505,8 +520,32 @@ 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 34f470779fa5d1cf9638431253024481236c073b..4f5b516144829a7ae11f21a56789ac7a1f256250 100644
--- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
+++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
@@ -332,6 +332,64 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
 
     }
 
+    // Paper start - incremental autosave
+    final it.unimi.dsi.fastutil.objects.ObjectRBTreeSet<PlayerChunk> autoSaveQueue = new it.unimi.dsi.fastutil.objects.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 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());
@@ -442,6 +500,7 @@ 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();
@@ -623,6 +682,8 @@ 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 ca0a23be27ee8174204867d463eb89a10931ff84..a0484d8062ecfb817cfd5b996915dc8f9a4eb2bd 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -817,11 +817,44 @@ public class WorldServer extends World {
         return this.worldProvider.c();
     }
 
+    // Paper start - derived from below
+    public void saveIncrementally(boolean doFull) throws ExceptionWorldConflict {
+        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
+
+
+            // CraftBukkit start - moved from MinecraftServer.saveChunks
+            // PAIL - rename
+            if (doFull) {
+                WorldServer worldserver1 = this;
+                WorldData worlddata = worldserver1.getWorldData();
+
+                worldserver1.getWorldBorder().save(worlddata);
+                worlddata.setCustomBossEvents(this.server.getBossBattleCustomData().save());
+                worldserver1.getDataManager().saveWorldData(worlddata, this.server.getPlayerList().save());
+                // CraftBukkit end
+            }
+        }
+    }
+    // Paper end
+
     public void save(@Nullable IProgressUpdate iprogressupdate, boolean flag, boolean flag1) throws ExceptionWorldConflict {
         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
             try (co.aikar.timings.Timing ignored = timings.worldSave.startTiming()) { // Paper
             if (iprogressupdate != null) {
                 iprogressupdate.a(new ChatMessage("menu.savingLevel", new Object[0]));
@@ -848,6 +881,7 @@ public class WorldServer extends World {
         // CraftBukkit end
     }
 
+    protected void saveData() throws ExceptionWorldConflict { this.m_(); } // Paper - OBFHELPER
     protected void m_() throws ExceptionWorldConflict {
         this.checkSession();
         this.worldProvider.i();
