Paper/patches/server/0031-Further-improve-server-tick-loop.patch
2023-10-26 16:34:58 -07:00

238 lines
13 KiB
Diff

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 6155d6e3c361bb4a0381e7065a7b603b783a47a6..d13a0f5a3b95b0d0ca80c760f757087c88eceaeb 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -277,7 +277,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
public OptionSet options;
public org.bukkit.command.ConsoleCommandSender console;
public ConsoleReader reader;
- public static int currentTick = (int) (System.currentTimeMillis() / 50);
+ 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 Commands vanillaCommandDispatcher;
@@ -286,7 +286,7 @@ 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
public final double[] recentTps = new double[ 3 ];
// Spigot end
public final io.papermc.paper.configuration.PaperConfigurations paperConfigurations;
@@ -933,6 +933,57 @@ 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
public static volatile RuntimeException chunkSystemCrash; // Paper - rewrite chunk system
@@ -949,7 +1000,8 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
// Spigot start
Arrays.fill( this.recentTps, 20 );
- long curTime, tickSection = Util.getMillis(), tickCount = 1;
+ long start = System.nanoTime(), curTime, tickSection = start; // Paper - Further improve server tick loop
+ lastTick = start - TICK_TIME; // Paper
while (this.running) {
// Paper start - rewrite chunk system
// guarantee that nothing can stop the server from halting if it can at least still tick
@@ -957,7 +1009,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
throw this.chunkSystemCrash;
}
// Paper end - rewrite chunk system
- long i = (curTime = Util.getMillis()) - this.nextTickTime;
+ long i = ((curTime = System.nanoTime()) / (1000L * 1000L)) - this.nextTickTime; // Paper
if (i > 5000L && this.nextTickTime - this.lastOverloadWarning >= 30000L) { // CraftBukkit
long j = i / 50L;
@@ -969,12 +1021,18 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
}
++MinecraftServer.currentTickLong; // Paper
- if ( tickCount++ % MinecraftServer.SAMPLE_INTERVAL == 0 )
+ if ( ++MinecraftServer.currentTick % MinecraftServer.SAMPLE_INTERVAL == 0 )
{
- 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)
+ final long diff = curTime - tickSection;
+ 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();
+ // Paper end
tickSection = curTime;
}
// Spigot end
@@ -984,7 +1042,8 @@ 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 = curTime;
this.nextTickTime += 50L;
this.startMetricsRecordingTick();
this.profiler.push("tick");
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index e2f17636045abf56c04567d8cd7f0dfcdeee0f7e..2aa305814e2207cd80cf4630fda8e1adf456db54 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -2478,6 +2478,17 @@ public final class CraftServer implements Server {
return CraftMagicNumbers.INSTANCE;
}
+ // Paper - Add getTPS API - Further improve tick loop
+ @Override
+ public double[] getTPS() {
+ 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 end
+
// Spigot start
private final org.bukkit.Server.Spigot spigot = new org.bukkit.Server.Spigot()
{
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
}
}