Paper/patches/server/0499-Incremental-player-saving.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 9 Aug 2020 08:59:25 +0300
Subject: [PATCH] Incremental player saving


diff --git a/src/main/java/com/destroystokyo/paper/PaperConfig.java b/src/main/java/com/destroystokyo/paper/PaperConfig.java
index 0ff0a71fe5dc53fa5fb81edffabc69790e3bcd1e..d74f0bdabd64976bf8608f2a5d8f2dc6118a35f2 100644
--- a/src/main/java/com/destroystokyo/paper/PaperConfig.java
+++ b/src/main/java/com/destroystokyo/paper/PaperConfig.java
@@ -462,4 +462,14 @@ public class PaperConfig {
         set("settings.unsupported-settings.allow-tnt-duplication", null);
     }
 
+    public static int playerAutoSaveRate = -1;
+    public static int maxPlayerAutoSavePerTick = 10;
+    private static void playerAutoSaveRate() {
+        playerAutoSaveRate = getInt("settings.player-auto-save-rate", -1);
+        maxPlayerAutoSavePerTick = getInt("settings.max-player-auto-save-per-tick", -1);
+        if (maxPlayerAutoSavePerTick == -1) { // -1 Automatic / "Recommended"
+            // 10 should be safe for everyone unless you mass spamming player auto save
+            maxPlayerAutoSavePerTick = (playerAutoSaveRate == -1 || playerAutoSaveRate > 100) ? 10 : 20;
+        }
+    }
 }
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 58652325de8c3978359a9864bb68da9347990774..4af56ca699d456eb23794673861323ab06cf6de8 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -981,7 +981,6 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
         if (this.playerList != null) {
             MinecraftServer.LOGGER.info("Saving players");
-            this.playerList.saveAll();
             this.playerList.removeAll(this.isRestarting); // Paper
             try { Thread.sleep(100); } catch (InterruptedException ex) {} // CraftBukkit - SPIGOT-625 - give server at least a chance to send packets
         }
@@ -1419,9 +1418,15 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         // if (this.autosavePeriod > 0 && this.tickCount % this.autosavePeriod == 0) { // CraftBukkit // Paper - move down
         //     MinecraftServer.LOGGER.debug("Autosave started"); // Paper
         serverAutoSave = (autosavePeriod > 0 && this.tickCount % autosavePeriod == 0); // Paper
+        // Paper start
+        int playerSaveInterval = com.destroystokyo.paper.PaperConfig.playerAutoSaveRate;
+        if (playerSaveInterval < 0) {
+            playerSaveInterval = autosavePeriod;
+        }
+        // Paper end
             this.profiler.push("save");
-        if (this.autosavePeriod > 0 && this.tickCount % this.autosavePeriod == 0) { // Paper - moved from above
-            this.playerList.saveAll();
+        if (playerSaveInterval > 0) { // Paper
+            this.playerList.savePlayers(playerSaveInterval); // Paper
             // this.saveAllChunks(true, false, false); // Paper - saved incrementally below
         } // Paper start
         for (ServerLevel level : this.getAllLevels()) {
diff --git a/src/main/java/net/minecraft/server/level/ServerPlayer.java b/src/main/java/net/minecraft/server/level/ServerPlayer.java
index 74b68679d311017246d49c37f3cd17f938f3b57f..d8df3bcf6ddd87e9fa932f01a41a48a641328f9d 100644
--- a/src/main/java/net/minecraft/server/level/ServerPlayer.java
+++ b/src/main/java/net/minecraft/server/level/ServerPlayer.java
@@ -175,6 +175,7 @@ public class ServerPlayer extends Player {
     public final int getViewDistance() { return this.getLevel().getChunkSource().chunkMap.viewDistance - 1; } // Paper - placeholder
 
     private static final Logger LOGGER = LogManager.getLogger();
+    public long lastSave = MinecraftServer.currentTick; // Paper
     private static final int NEUTRAL_MOB_DEATH_NOTIFICATION_RADII_XZ = 32;
     private static final int NEUTRAL_MOB_DEATH_NOTIFICATION_RADII_Y = 10;
     public ServerGamePacketListenerImpl connection;
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index 476a3a317779fdecbced48caa85f6835c54eb018..9a73364f4d56f3a7cecb27bc8034166b8f5731b9 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -570,6 +570,7 @@ public abstract class PlayerList {
     protected void save(ServerPlayer player) {
         if (!player.getBukkitEntity().isPersistent()) return; // CraftBukkit
         if (!player.didPlayerJoinEvent) return; // Paper - If we never fired PJE, we disconnected during login. Data has not changed, and additionally, our saved vehicle is not loaded! If we save now, we will lose our vehicle (CraftBukkit bug)
+        player.lastSave = MinecraftServer.currentTick; // Paper
         this.playerIo.save(player);
         ServerStatsCounter serverstatisticmanager = (ServerStatsCounter) player.getStats(); // CraftBukkit
 
@@ -1208,10 +1209,21 @@ public abstract class PlayerList {
     }
 
     public void saveAll() {
-        net.minecraft.server.MCUtil.ensureMain("Save Players" , () -> { // Paper - Ensure main
+        // Paper start - incremental player saving
+        savePlayers(null);
+    }
+    public void savePlayers(Integer interval) {
+        MCUtil.ensureMain("Save Players" , () -> { // Paper - Ensure main
         MinecraftTimings.savePlayers.startTiming(); // Paper
+        int numSaved = 0;
+        long now = MinecraftServer.currentTick;
         for (int i = 0; i < this.players.size(); ++i) {
-            this.save(this.players.get(i));
+            ServerPlayer entityplayer = this.players.get(i);
+            if (interval == null || now - entityplayer.lastSave >= interval) {
+                this.save(entityplayer);
+                if (interval != null && ++numSaved <= com.destroystokyo.paper.PaperConfig.maxPlayerAutoSavePerTick) { break; }
+            }
+            // Paper end
         }
         MinecraftTimings.savePlayers.stopTiming(); // Paper
         return null; }); // Paper - ensure main