459987d69f
improved the water code so that immunity wont trigger if the entity has the water pathfinder system active, so this improves support for all entities that know how to behave in water. Merged 2 EAR patches together, and removed an MCUtil method that doesnt have a purpose anymore
68 Zeilen
3.0 KiB
Diff
68 Zeilen
3.0 KiB
Diff
From dddfa3385a6f08eb4bba4dcaf6ef11570db9c0f5 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 c0ab543b91..15666325ea 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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2.19.0
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