From 0d18b153933291178929caabd1218c77827415f4 Mon Sep 17 00:00:00 2001 From: Spottedleaf Date: Sat, 22 Feb 2020 07:07:40 -0800 Subject: [PATCH] Workaround for replacing PlayerChunkMap#visibleChunks field I run a fork of paper which replaces the visibleChunks and updatingChunks field for gc performance reasons - visibleChunks is updated via cloning updatingChunks, and at high chunk counts this causes gc issues due to the humongous allocation. Unfortunately the only solution is to not clone the map - which is why the field is removed. Instead of BukkitAdapter#getPlayerChunk using the visibleChunks field, it now uses a MethodHandle for PlayerChunkMap#getVisibleChunk. This method is present on spigot & paper (only protected on spigot - which is why reflection is required), and I preserve the same thread-safety it provides in my fork - so this solution will not break compatibility with craftbukkit, spigot, and paper. --- .../adapter/mc1_15_2/BukkitAdapter_1_15_2.java | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/worldedit-bukkit/src/main/java/com/boydti/fawe/bukkit/adapter/mc1_15_2/BukkitAdapter_1_15_2.java b/worldedit-bukkit/src/main/java/com/boydti/fawe/bukkit/adapter/mc1_15_2/BukkitAdapter_1_15_2.java index e42b624fd..4e67ef329 100644 --- a/worldedit-bukkit/src/main/java/com/boydti/fawe/bukkit/adapter/mc1_15_2/BukkitAdapter_1_15_2.java +++ b/worldedit-bukkit/src/main/java/com/boydti/fawe/bukkit/adapter/mc1_15_2/BukkitAdapter_1_15_2.java @@ -12,6 +12,10 @@ import com.boydti.fawe.util.TaskManager; import com.sk89q.worldedit.world.block.BlockState; import com.sk89q.worldedit.world.block.BlockTypesCache; import io.papermc.lib.PaperLib; +import java.lang.invoke.MethodHandle; +import java.lang.invoke.MethodHandles; +import java.lang.invoke.MethodType; +import java.lang.reflect.Method; import java.util.concurrent.locks.ReentrantLock; import net.jpountz.util.UnsafeUtils; import net.minecraft.server.v1_15_R1.*; @@ -40,6 +44,8 @@ public final class BukkitAdapter_1_15_2 extends NMSAdapter { private final static Field fieldDirtyCount; private final static Field fieldDirtyBits; + private final static MethodHandle methodGetVisibleChunk; + private static final int CHUNKSECTION_BASE; private static final int CHUNKSECTION_SHIFT; @@ -66,6 +72,10 @@ public final class BukkitAdapter_1_15_2 extends NMSAdapter { fieldDirtyBits = PlayerChunk.class.getDeclaredField("r"); fieldDirtyBits.setAccessible(true); + Method declaredGetVisibleChunk = PlayerChunkMap.class.getDeclaredMethod("getVisibleChunk", long.class); + declaredGetVisibleChunk.setAccessible(true); + methodGetVisibleChunk = MethodHandles.lookup().unreflect(declaredGetVisibleChunk); + Field tmp = DataPaletteBlock.class.getDeclaredField("j"); ReflectionUtils.setAccessibleNonFinal(tmp); fieldLock = tmp; @@ -136,8 +146,11 @@ public final class BukkitAdapter_1_15_2 extends NMSAdapter { public static PlayerChunk getPlayerChunk(WorldServer nmsWorld, final int cx, final int cz) { PlayerChunkMap chunkMap = nmsWorld.getChunkProvider().playerChunkMap; - PlayerChunk playerChunk = chunkMap.visibleChunks.get(ChunkCoordIntPair.pair(cx, cz)); - return playerChunk; + try { + return (PlayerChunk)methodGetVisibleChunk.invoke(chunkMap, ChunkCoordIntPair.pair(cx, cz)); + } catch (Throwable thr) { + throw new RuntimeException(thr); + } } public static void sendChunk(WorldServer nmsWorld, int X, int Z, int mask) {