Upstream has released updates that appears to apply and compile correctly. This update has not been tested by PaperMC and as with ANY update, please do your own testing Developers!: You will need to clean up your work/Minecraft/1.13.2 folder for this Also, restore a patch that was dropped in the last upstream Bukkit Changes: 279eeab3 Fix command description not being set 96e2bb18 Remove debug print from SyntheticEventTest CraftBukkit Changes: d3ed1516 Fix dangerously threaded beacons 217a293d Don't relocate joptsimple to allow --help to work. 1be05a21 Prepare for imminent Java 12 release a49270b2 Mappings Update 5259d80c SPIGOT-4669: Fix PlayerTeleportEvent coordinates for relative teleports Spigot Changes: e6eb36f2 Rebuild patches
68 lines
3 KiB
Diff
68 lines
3 KiB
Diff
From ef3479c926dcb3b18351f3d163558c9b1d86aa58 Mon Sep 17 00:00:00 2001
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From: Aikar <aikar@aikar.co>
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Date: Mon, 23 Jul 2018 23:40:04 -0400
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Subject: [PATCH] Optimize Region File Cache
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CraftBukkit added synchronization to read and write methods. This adds
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much more contention on this object for accessing region files, as
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the entire read and write of NBT data is now a blocking operation.
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This causes issues when something then simply needs to check if a chunk exists
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on the main thread, causing a block...
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However, this synchronization was unnecessary, because there is already
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enough synchronization done to keep things safe
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1) Obtaining a Region File: Those methods are still static synchronized.
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Meaning we can safely obtain a Region File concurrently.
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2) RegionFile data access: Methods reading and manipulating data from
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a region file are also marked synchronized, ensuring that no 2 processes
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are reading or writing data at the same time.
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3) Checking a region file for chunkExists: getOffset is also synchronized
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ensuring that even if a chunk is currently being written, it will be safe.
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By removing these synchronizations, we reduce the locking to only
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when data is being write or read.
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GZIP compression and NBT Buffer creation will no longer be part of the
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synchronized context, reducing lock times.
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Ultimately: This brings us back to Vanilla, which has had no indication of region file loss.
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diff --git a/src/main/java/net/minecraft/server/RegionFileCache.java b/src/main/java/net/minecraft/server/RegionFileCache.java
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index 964996976..d07222239 100644
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--- a/src/main/java/net/minecraft/server/RegionFileCache.java
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+++ b/src/main/java/net/minecraft/server/RegionFileCache.java
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@@ -99,7 +99,7 @@ public class RegionFileCache {
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@Nullable
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// CraftBukkit start - call sites hoisted for synchronization
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- public static synchronized NBTTagCompound read(File file, int i, int j) throws IOException {
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+ public static NBTTagCompound read(File file, int i, int j) throws IOException { // Paper - remove synchronization
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RegionFile regionfile = a(file, i, j);
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DataInputStream datainputstream = regionfile.a(i & 31, j & 31);
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@@ -112,7 +112,7 @@ public class RegionFileCache {
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}
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@Nullable
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- public static synchronized void write(File file, int i, int j, NBTTagCompound nbttagcompound) throws IOException {
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+ public static void write(File file, int i, int j, NBTTagCompound nbttagcompound) throws IOException {
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int attempts = 0; Exception laste = null; while (attempts++ < 5) { try { // Paper
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RegionFile regionfile = a(file, i, j);
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@@ -138,7 +138,7 @@ public class RegionFileCache {
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// Paper end
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}
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- public static synchronized boolean chunkExists(File file, int i, int j) {
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+ public static boolean chunkExists(File file, int i, int j) { // Paper - remove synchronization
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RegionFile regionfile = b(file, i, j);
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return regionfile != null ? regionfile.d(i & 31, j & 31) : false;
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--
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2.21.0
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