Paper/Spigot-Server-Patches/0023-Further-improve-server-tick-loop.patch
Aikar 20e92f90d4
Disable the memory information in /tps unless argument is passed
Memory usage is a pretty useless value in any modern garbage collector
as the way memory is used makes this information not representive of
any actionable data.

In the recommended GC flags, this memory value will constantly rise until
it is near max and then goes down. This is perfectly normal and expected.

Having this information shown will lead to confusion.

Plus, many servers give this command to end users, which now really might
not want to expose this memory data.

So this disables it unless /tps mem is used, and also requires a permission
node to even run this subcommand.
2020-06-28 01:34:28 -04:00

209 Zeilen
11 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 1fcdbbbc7b60edd1e87bab5f1c5d19a6755de17c..0f2011a776619301dd6a133b9a4044b4f5b69cfc 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -144,7 +144,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
public org.bukkit.command.ConsoleCommandSender console;
public org.bukkit.command.RemoteConsoleCommandSender remoteConsole;
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 CommandDispatcher vanillaCommandDispatcher;
@@ -153,7 +153,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
// Spigot start
public static final int TPS = 20;
public static final int TICK_TIME = 1000000000 / TPS;
- private static final int SAMPLE_INTERVAL = 100;
+ private static final int SAMPLE_INTERVAL = 20; // Paper
public final double[] recentTps = new double[ 3 ];
public final SlackActivityAccountant slackActivityAccountant = new SlackActivityAccountant();
// Spigot end
@@ -807,6 +807,57 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
{
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 v() {
@@ -819,30 +870,38 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
// Spigot start
Arrays.fill( recentTps, 20 );
- long curTime, tickSection = SystemUtils.getMonotonicMillis(), tickCount = 1;
+ long start = System.nanoTime(), curTime, tickSection = start; // Paper - Further improve server tick loop
+ lastTick = start - TICK_TIME; // Paper
while (this.isRunning) {
- long i = (curTime = SystemUtils.getMonotonicMillis()) - this.nextTick;
+ long i = ((curTime = System.nanoTime()) / (1000L * 1000L)) - this.nextTick; // Paper
if (i > 5000L && this.nextTick - this.lastOverloadTime >= 30000L) { // CraftBukkit
long j = i / 50L;
if (server.getWarnOnOverload()) // CraftBukkit
- MinecraftServer.LOGGER.warn("Can't keep up! Is the server overloaded? Running {}ms or {} ticks behind", i, j);
+ MinecraftServer.LOGGER.warn("Can't keep up! Is the server overloaded? Running {}ms or {} ticks behind", i, j);
this.nextTick += j * 50L;
this.lastOverloadTime = this.nextTick;
}
- if ( tickCount++ % SAMPLE_INTERVAL == 0 )
+ if ( ++MinecraftServer.currentTick % SAMPLE_INTERVAL == 0 )
{
- double currentTps = 1E3 / ( curTime - tickSection ) * SAMPLE_INTERVAL;
- recentTps[0] = calcTps( recentTps[0], 0.92, currentTps ); // 1/exp(5sec/1min)
- recentTps[1] = calcTps( recentTps[1], 0.9835, currentTps ); // 1/exp(5sec/5min)
- recentTps[2] = calcTps( 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
+ recentTps[0] = tps1.getAverage();
+ recentTps[1] = tps5.getAverage();
+ recentTps[2] = tps15.getAverage();
+ // Paper end
tickSection = curTime;
}
// Spigot end
- MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit
+ //MinecraftServer.currentTick = (int) (System.currentTimeMillis() / 50); // CraftBukkit // Paper - don't overwrite current tick time
+ lastTick = curTime;
this.nextTick += 50L;
GameProfilerTick gameprofilertick = GameProfilerTick.a("Server");
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index e531fe5e77901e6478554c6269a83028e391db5f..0d28a442e0ffb524140208710b253ca88ae21f90 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -2045,6 +2045,17 @@ 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
+
private final Spigot spigot = new Spigot()
{
diff --git a/src/main/java/org/spigotmc/TicksPerSecondCommand.java b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
index 9cd57c9d5fe59ceb2cd307e4e1a2052c9ac428fe..7218f23df4d06ff1ca612286e4a404246389ab18 100644
--- a/src/main/java/org/spigotmc/TicksPerSecondCommand.java
+++ b/src/main/java/org/spigotmc/TicksPerSecondCommand.java
@@ -26,22 +26,30 @@ 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( format( tps ) );
- sb.append( ", " );
+ // Paper start - Further improve tick handling
+ double[] tps = org.bukkit.Bukkit.getTPS();
+ String[] tpsAvg = new String[tps.length];
+
+ for ( int i = 0; i < tps.length; i++) {
+ tpsAvg[i] = format( tps[i] );
+ }
+ sender.sendMessage(ChatColor.GOLD + "TPS from last 1m, 5m, 15m: " + org.apache.commons.lang.StringUtils.join(tpsAvg, ", "));
+ if (args.length > 0 && args[0].equals("mem") && sender.hasPermission("bukkit.command.tpsmemory")) {
+ 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)");
+ if (!hasShownMemoryWarning) {
+ sender.sendMessage(ChatColor.RED + "Warning: " + ChatColor.GOLD + " 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.");
+ 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 String 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 );
+ + ( ( tps > 21.0 ) ? "*" : "" ) + Math.min( Math.round( tps * 100.0 ) / 100.0, 20.0 ); // Paper - only print * at 21, we commonly peak to 20.02 as the tick sleep is not accurate enough, stop the noise
}
}