aboutsummaryrefslogtreecommitdiffhomepage
path: root/patches/server/0023-Further-improve-server-tick-loop.patch
blob: ff1c5e21de1c5d91fecd30dc8dab407633b9243f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Tue, 1 Mar 2016 23:09:29 -0600
Subject: [PATCH] Further improve server tick loop

Improves how the catchup buffer is handled, allowing it to roll both ways
increasing the effeciency of the thread sleep so it only will sleep once.

Also increases the buffer of the catchup to ensure server stays at 20 TPS unless extreme conditions

Previous implementation did not calculate TPS correctly.
Switch to a realistic rolling average and factor in std deviation as an extra reporting variable

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 8acd27005f2b7cf32dc4cf93cf1a6eea2ab594ca..f307408d459196caafc0a485ddb8d1c00bdf0af9 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -307,7 +307,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     public org.bukkit.craftbukkit.CraftServer server;
     public OptionSet options;
     public org.bukkit.command.ConsoleCommandSender console;
-    public static int currentTick = (int) (System.currentTimeMillis() / 50);
+    public static int currentTick; // Paper - improve tick loop
     public java.util.Queue<Runnable> processQueue = new java.util.concurrent.ConcurrentLinkedQueue<Runnable>();
     public int autosavePeriod;
     public Commands vanillaCommandDispatcher;
@@ -316,7 +316,8 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     // Spigot start
     public static final int TPS = 20;
     public static final int TICK_TIME = 1000000000 / MinecraftServer.TPS;
-    private static final int SAMPLE_INTERVAL = 100;
+    private static final int SAMPLE_INTERVAL = 20; // Paper - improve server tick loop
+    @Deprecated(forRemoval = true) // Paper
     public final double[] recentTps = new double[ 3 ];
     // Spigot end
     public final io.papermc.paper.configuration.PaperConfigurations paperConfigurations; // Paper - add paper configuration files
@@ -1033,6 +1034,57 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     {
         return ( avg * exp ) + ( tps * ( 1 - exp ) );
     }
+
+    // Paper start - Further improve server tick loop
+    private static final long SEC_IN_NANO = 1000000000;
+    private static final long MAX_CATCHUP_BUFFER = TICK_TIME * TPS * 60L;
+    private long lastTick = 0;
+    private long catchupTime = 0;
+    public final RollingAverage tps1 = new RollingAverage(60);
+    public final RollingAverage tps5 = new RollingAverage(60 * 5);
+    public final RollingAverage tps15 = new RollingAverage(60 * 15);
+
+    public static class RollingAverage {
+        private final int size;
+        private long time;
+        private java.math.BigDecimal total;
+        private int index = 0;
+        private final java.math.BigDecimal[] samples;
+        private final long[] times;
+
+        RollingAverage(int size) {
+            this.size = size;
+            this.time = size * SEC_IN_NANO;
+            this.total = dec(TPS).multiply(dec(SEC_IN_NANO)).multiply(dec(size));
+            this.samples = new java.math.BigDecimal[size];
+            this.times = new long[size];
+            for (int i = 0; i < size; i++) {
+                this.samples[i] = dec(TPS);
+                this.times[i] = SEC_IN_NANO;
+            }
+        }
+
+        private static java.math.BigDecimal dec(long t) {
+            return new java.math.BigDecimal(t);
+        }
+        public void add(java.math.BigDecimal x, long t) {
+            time -= times[index];
+            total = total.subtract(samples[index].multiply(dec(times[index])));
+            samples[index] = x;
+            times[index] = t;
+            time += t;
+            total = total.add(x.multiply(dec(t)));
+            if (++index == size) {
+                index = 0;
+            }
+        }
+
+        public double getAverage() {
+            return total.divide(dec(time), 30, java.math.RoundingMode.HALF_UP).doubleValue();
+        }
+    }
+    private static final java.math.BigDecimal TPS_BASE = new java.math.BigDecimal(1E9).multiply(new java.math.BigDecimal(SAMPLE_INTERVAL));
+    // Paper end
     // Spigot End
 
     protected void runServer() {
@@ -1047,7 +1099,10 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
 
             // Spigot start
             Arrays.fill( this.recentTps, 20 );
-            long tickSection = Util.getMillis(), tickCount = 1;
+            // Paper start - further improve server tick loop
+            long tickSection = Util.getNanos();
+            long currentTime;
+            // Paper end - further improve server tick loop
             while (this.running) {
                 long i;
 
@@ -1069,15 +1124,22 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                     }
                 }
                 // Spigot start
-                if ( tickCount++ % MinecraftServer.SAMPLE_INTERVAL == 0 )
-                {
-                    long curTime = Util.getMillis();
-                    double currentTps = 1E3 / ( curTime - tickSection ) * MinecraftServer.SAMPLE_INTERVAL;
-                    this.recentTps[0] = MinecraftServer.calcTps( this.recentTps[0], 0.92, currentTps ); // 1/exp(5sec/1min)
-                    this.recentTps[1] = MinecraftServer.calcTps( this.recentTps[1], 0.9835, currentTps ); // 1/exp(5sec/5min)
-                    this.recentTps[2] = MinecraftServer.calcTps( this.recentTps[2], 0.9945, currentTps ); // 1/exp(5sec/15min)
-                    tickSection = curTime;
+                // Paper start - further improve server tick loop
+                currentTime = Util.getNanos();
+                if (++MinecraftServer.currentTick % MinecraftServer.SAMPLE_INTERVAL == 0) {
+                    final long diff = currentTime - tickSection;
+                    final java.math.BigDecimal currentTps = TPS_BASE.divide(new java.math.BigDecimal(diff), 30, java.math.RoundingMode.HALF_UP);
+                    tps1.add(currentTps, diff);
+                    tps5.add(currentTps, diff);
+                    tps15.add(currentTps, diff);
+
+                    // Backwards compat with bad plugins
+                    this.recentTps[0] = tps1.getAverage();
+                    this.recentTps[1] = tps5.getAverage();
+                    this.recentTps[2] = tps15.getAverage();
+                    tickSection = currentTime;
                 }
+                // Paper end - further improve server tick loop
                 // Spigot end
 
                 boolean flag = i == 0L;
@@ -1087,7 +1149,8 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                     this.debugCommandProfiler = new MinecraftServer.TimeProfiler(Util.getNanos(), this.tickCount);
                 }
 
-                MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit
+                //MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit // Paper - don't overwrite current tick time
+                lastTick = currentTime;
                 this.nextTickTimeNanos += i;
 
                 try {
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index 5c54c5c525c86bb8037982435b8769ec2ca2c6cb..c9920b60a536f5735c61fd7ef154569f6b04c58b 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -2680,7 +2680,11 @@ public final class CraftServer implements Server {
 
     @Override
     public double[] getTPS() {
-        return new double[]{0, 0, 0}; // TODO
+        return new double[] {
+            net.minecraft.server.MinecraftServer.getServer().tps1.getAverage(),
+            net.minecraft.server.MinecraftServer.getServer().tps5.getAverage(),
+            net.minecraft.server.MinecraftServer.getServer().tps15.getAverage()
+        };
     }
 
     // Paper start - adventure sounds
diff --git a/src/main/java/org/spigotmc/TicksPerSecondCommand.java b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
index d9ec48be0fdd2bfea938aa29e36b0f6ffa839ab2..9eb2823cc8f83bad2626fc77578b0162d9ed5782 100644
--- a/src/main/java/org/spigotmc/TicksPerSecondCommand.java
+++ b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
@@ -15,6 +15,12 @@ public class TicksPerSecondCommand extends Command
         this.usageMessage = "/tps";
         this.setPermission( "bukkit.command.tps" );
     }
+    // Paper start
+    private static final net.kyori.adventure.text.Component WARN_MSG = net.kyori.adventure.text.Component.text()
+        .append(net.kyori.adventure.text.Component.text("Warning: ", net.kyori.adventure.text.format.NamedTextColor.RED))
+        .append(net.kyori.adventure.text.Component.text("Memory usage on modern garbage collectors is not a stable value and it is perfectly normal to see it reach max. Please do not pay it much attention.", net.kyori.adventure.text.format.NamedTextColor.GOLD))
+        .build();
+    // Paper end
 
     @Override
     public boolean execute(CommandSender sender, String currentAlias, String[] args)
@@ -24,22 +30,40 @@ public class TicksPerSecondCommand extends Command
             return true;
         }
 
-        StringBuilder sb = new StringBuilder( ChatColor.GOLD + "TPS from last 1m, 5m, 15m: " );
-        for ( double tps : MinecraftServer.getServer().recentTps )
-        {
-            sb.append( this.format( tps ) );
-            sb.append( ", " );
+        // Paper start - Further improve tick handling
+        double[] tps = org.bukkit.Bukkit.getTPS();
+        net.kyori.adventure.text.Component[] tpsAvg = new net.kyori.adventure.text.Component[tps.length];
+
+        for ( int i = 0; i < tps.length; i++) {
+            tpsAvg[i] = TicksPerSecondCommand.format( tps[i] );
+        }
+
+        net.kyori.adventure.text.TextComponent.Builder builder = net.kyori.adventure.text.Component.text();
+        builder.append(net.kyori.adventure.text.Component.text("TPS from last 1m, 5m, 15m: ", net.kyori.adventure.text.format.NamedTextColor.GOLD));
+        builder.append(net.kyori.adventure.text.Component.join(net.kyori.adventure.text.JoinConfiguration.commas(true), tpsAvg));
+        sender.sendMessage(builder.asComponent());
+        if (args.length > 0 && args[0].equals("mem") && sender.hasPermission("bukkit.command.tpsmemory")) {
+            sender.sendMessage(net.kyori.adventure.text.Component.text()
+                .append(net.kyori.adventure.text.Component.text("Current Memory Usage: ", net.kyori.adventure.text.format.NamedTextColor.GOLD))
+                .append(net.kyori.adventure.text.Component.text(((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) / (1024 * 1024)) + "/" + (Runtime.getRuntime().totalMemory() / (1024 * 1024)) + " mb (Max: " + (Runtime.getRuntime().maxMemory() / (1024 * 1024)) + " mb)", net.kyori.adventure.text.format.NamedTextColor.GREEN))
+            );
+            if (!this.hasShownMemoryWarning) {
+                sender.sendMessage(WARN_MSG);
+                this.hasShownMemoryWarning = true;
+            }
         }
-        sender.sendMessage( sb.substring( 0, sb.length() - 2 ) );
-        sender.sendMessage(ChatColor.GOLD + "Current Memory Usage: " + ChatColor.GREEN + ((Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) / (1024 * 1024)) + "/" + (Runtime.getRuntime().totalMemory() / (1024 * 1024)) + " mb (Max: "
-                + (Runtime.getRuntime().maxMemory() / (1024 * 1024)) + " mb)");
+        // Paper end
 
         return true;
     }
 
-    private String format(double tps)
+    private boolean hasShownMemoryWarning; // Paper
+    private static net.kyori.adventure.text.Component format(double tps) // Paper - Made static
     {
-        return ( ( tps > 18.0 ) ? ChatColor.GREEN : ( tps > 16.0 ) ? ChatColor.YELLOW : ChatColor.RED ).toString()
-                + ( ( tps > 20.0 ) ? "*" : "" ) + Math.min( Math.round( tps * 100.0 ) / 100.0, 20.0 );
+        // Paper
+        net.kyori.adventure.text.format.TextColor color = ( ( tps > 18.0 ) ? net.kyori.adventure.text.format.NamedTextColor.GREEN : ( tps > 16.0 ) ? net.kyori.adventure.text.format.NamedTextColor.YELLOW : net.kyori.adventure.text.format.NamedTextColor.RED );
+        String amount = Math.min(Math.round(tps * 100.0) / 100.0, 20.0) + (tps > 21.0  ? "*" : ""); // Paper - only print * at 21, we commonly peak to 20.02 as the tick sleep is not accurate enough, stop the noise
+        return net.kyori.adventure.text.Component.text(amount, color);
+        // Paper end
     }
 }