PaperMC/patches/server/0436-Optimize-Bit-Operations-by-inlining.patch
Spottedleaf 01a13871de
Rewrite chunk system (#8177)
Patch documentation to come

Issues with the old system that are fixed now:
- World generation does not scale with cpu cores effectively.
- Relies on the main thread for scheduling and maintaining chunk state, dropping chunk load/generate rates at lower tps.
- Unreliable prioritisation of chunk gen/load calls that block the main thread.
- Shutdown logic is utterly unreliable, as it has to wait for all chunks to unload - is it guaranteed that the chunk system is in a state on shutdown that it can reliably do this? Watchdog shutdown also typically failed due to thread checks, which is now resolved.
- Saving of data is not unified (i.e can save chunk data without saving entity data, poses problems for desync if shutdown is really abnormal.
- Entities are not loaded with chunks. This caused quite a bit of headache for Chunk#getEntities API, but now the new chunk system loads entities with chunks so that they are ready whenever the chunk loads in. Effectively brings the behavior back to 1.16 era, but still storing entities in their own separate regionfiles.

The above list is not complete. The patch documentation will complete it.

New chunk system hard relies on starlight and dataconverter, and most importantly the new concurrent utilities in ConcurrentUtil.

Some of the old async chunk i/o interface (i.e the old file io thread reroutes _some_ calls to the new file io thread) is kept for plugin compat reasons. It will be removed in the next major version of minecraft.

The old legacy chunk system patches have been moved to the removed folder in case we need them again.
2022-09-26 01:02:51 -07:00

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Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 4 Jun 2020 02:24:49 -0400
Subject: [PATCH] Optimize Bit Operations by inlining
Inline bit operations and reduce instruction count to make these hot
operations faster
diff --git a/src/main/java/net/minecraft/core/BlockPos.java b/src/main/java/net/minecraft/core/BlockPos.java
index f8361dcf9d0378497ec5a34ea53b4e0019700851..e68cd32a7db88f29d3224b0908119232ab3cf71a 100644
--- a/src/main/java/net/minecraft/core/BlockPos.java
+++ b/src/main/java/net/minecraft/core/BlockPos.java
@@ -30,15 +30,16 @@ public class BlockPos extends Vec3i {
}).stable();
private static final Logger LOGGER = LogUtils.getLogger();
public static final BlockPos ZERO = new BlockPos(0, 0, 0);
- private static final int PACKED_X_LENGTH = 1 + Mth.log2(Mth.smallestEncompassingPowerOfTwo(30000000));
- private static final int PACKED_Z_LENGTH = PACKED_X_LENGTH;
- public static final int PACKED_Y_LENGTH = 64 - PACKED_X_LENGTH - PACKED_Z_LENGTH;
- private static final long PACKED_X_MASK = (1L << PACKED_X_LENGTH) - 1L;
- private static final long PACKED_Y_MASK = (1L << PACKED_Y_LENGTH) - 1L;
- private static final long PACKED_Z_MASK = (1L << PACKED_Z_LENGTH) - 1L;
- private static final int Y_OFFSET = 0;
- private static final int Z_OFFSET = PACKED_Y_LENGTH;
- private static final int X_OFFSET = PACKED_Y_LENGTH + PACKED_Z_LENGTH;
+ // Paper start - static constants
+ private static final int PACKED_X_LENGTH = 26;
+ private static final int PACKED_Z_LENGTH = 26;
+ public static final int PACKED_Y_LENGTH = 12;
+ private static final long PACKED_X_MASK = 67108863;
+ private static final long PACKED_Y_MASK = 4095;
+ private static final long PACKED_Z_MASK = 67108863;
+ private static final int Z_OFFSET = 12;
+ private static final int X_OFFSET = 38;
+ // Paper end
public BlockPos(int x, int y, int z) {
super(x, y, z);
@@ -60,28 +61,29 @@ public class BlockPos extends Vec3i {
this(pos.getX(), pos.getY(), pos.getZ());
}
+ public static long getAdjacent(int baseX, int baseY, int baseZ, Direction enumdirection) { return asLong(baseX + enumdirection.getStepX(), baseY + enumdirection.getStepY(), baseZ + enumdirection.getStepZ()); } // Paper
public static long offset(long value, Direction direction) {
return offset(value, direction.getStepX(), direction.getStepY(), direction.getStepZ());
}
public static long offset(long value, int x, int y, int z) {
- return asLong(getX(value) + x, getY(value) + y, getZ(value) + z);
+ return asLong((int) (value >> 38) + x, (int) ((value << 52) >> 52) + y, (int) ((value << 26) >> 38) + z); // Paper - simplify/inline
}
public static int getX(long packedPos) {
- return (int)(packedPos << 64 - X_OFFSET - PACKED_X_LENGTH >> 64 - PACKED_X_LENGTH);
+ return (int) (packedPos >> 38); // Paper - simplify/inline
}
public static int getY(long packedPos) {
- return (int)(packedPos << 64 - PACKED_Y_LENGTH >> 64 - PACKED_Y_LENGTH);
+ return (int) ((packedPos << 52) >> 52); // Paper - simplify/inline
}
public static int getZ(long packedPos) {
- return (int)(packedPos << 64 - Z_OFFSET - PACKED_Z_LENGTH >> 64 - PACKED_Z_LENGTH);
+ return (int) ((packedPos << 26) >> 38); // Paper - simplify/inline
}
public static BlockPos of(long packedPos) {
- return new BlockPos(getX(packedPos), getY(packedPos), getZ(packedPos));
+ return new BlockPos((int) (packedPos >> 38), (int) ((packedPos << 52) >> 52), (int) ((packedPos << 26) >> 38)); // Paper - simplify/inline
}
public long asLong() {
@@ -89,10 +91,7 @@ public class BlockPos extends Vec3i {
}
public static long asLong(int x, int y, int z) {
- long l = 0L;
- l |= ((long)x & PACKED_X_MASK) << X_OFFSET;
- l |= ((long)y & PACKED_Y_MASK) << 0;
- return l | ((long)z & PACKED_Z_MASK) << Z_OFFSET;
+ return (((long) x & (long) 67108863) << 38) | (((long) y & (long) 4095)) | (((long) z & (long) 67108863) << 12); // Paper - inline constants and simplify
}
public static long getFlatIndex(long y) {
diff --git a/src/main/java/net/minecraft/core/SectionPos.java b/src/main/java/net/minecraft/core/SectionPos.java
index a481bd6328fe9e66f6911bf32ed11947c504c93c..a9d0d72aad7b1b708617a082c5efcd881a0f00d3 100644
--- a/src/main/java/net/minecraft/core/SectionPos.java
+++ b/src/main/java/net/minecraft/core/SectionPos.java
@@ -38,7 +38,7 @@ public class SectionPos extends Vec3i {
}
public static SectionPos of(BlockPos pos) {
- return new SectionPos(blockToSectionCoord(pos.getX()), blockToSectionCoord(pos.getY()), blockToSectionCoord(pos.getZ()));
+ return new SectionPos(pos.getX() >> 4, pos.getY() >> 4, pos.getZ() >> 4); // Paper
}
public static SectionPos of(ChunkPos chunkPos, int y) {
@@ -54,7 +54,7 @@ public class SectionPos extends Vec3i {
}
public static SectionPos of(long packed) {
- return new SectionPos(x(packed), y(packed), z(packed));
+ return new SectionPos((int) (packed >> 42), (int) (packed << 44 >> 44), (int) (packed << 22 >> 42)); // Paper
}
public static SectionPos bottomOf(ChunkAccess chunk) {
@@ -65,8 +65,16 @@ public class SectionPos extends Vec3i {
return offset(packed, direction.getStepX(), direction.getStepY(), direction.getStepZ());
}
+ // Paper start
+ public static long getAdjacentFromBlockPos(int x, int y, int z, Direction enumdirection) {
+ return (((long) ((x >> 4) + enumdirection.getStepX()) & 4194303L) << 42) | (((long) ((y >> 4) + enumdirection.getStepY()) & 1048575L)) | (((long) ((z >> 4) + enumdirection.getStepZ()) & 4194303L) << 20);
+ }
+ public static long getAdjacentFromSectionPos(int x, int y, int z, Direction enumdirection) {
+ return (((long) (x + enumdirection.getStepX()) & 4194303L) << 42) | (((long) ((y) + enumdirection.getStepY()) & 1048575L)) | (((long) (z + enumdirection.getStepZ()) & 4194303L) << 20);
+ }
+ // Paper end
public static long offset(long packed, int x, int y, int z) {
- return asLong(x(packed) + x, y(packed) + y, z(packed) + z);
+ return (((long) ((int) (packed >> 42) + x) & 4194303L) << 42) | (((long) ((int) (packed << 44 >> 44) + y) & 1048575L)) | (((long) ((int) (packed << 22 >> 42) + z) & 4194303L) << 20); // Simplify to reduce instruction count
}
public static int posToSectionCoord(double coord) {
@@ -86,10 +94,7 @@ public class SectionPos extends Vec3i {
}
public static short sectionRelativePos(BlockPos pos) {
- int i = sectionRelative(pos.getX());
- int j = sectionRelative(pos.getY());
- int k = sectionRelative(pos.getZ());
- return (short)(i << 8 | k << 4 | j << 0);
+ return (short) ((pos.getX() & 15) << 8 | (pos.getZ() & 15) << 4 | pos.getY() & 15); // Paper - simplify/inline
}
public static int sectionRelativeX(short packedLocalPos) {
@@ -152,16 +157,16 @@ public class SectionPos extends Vec3i {
return this.getZ();
}
- public int minBlockX() {
- return sectionToBlockCoord(this.x());
+ public final int minBlockX() { // Paper - make final
+ return this.getX() << 4; // Paper - inline
}
- public int minBlockY() {
- return sectionToBlockCoord(this.y());
+ public final int minBlockY() { // Paper - make final
+ return this.getY() << 4; // Paper - inline
}
- public int minBlockZ() {
- return sectionToBlockCoord(this.z());
+ public int minBlockZ() { // Paper - make final
+ return this.getZ() << 4; // Paper - inline
}
public int maxBlockX() {
@@ -177,7 +182,8 @@ public class SectionPos extends Vec3i {
}
public static long blockToSection(long blockPos) {
- return asLong(blockToSectionCoord(BlockPos.getX(blockPos)), blockToSectionCoord(BlockPos.getY(blockPos)), blockToSectionCoord(BlockPos.getZ(blockPos)));
+ // b(a(BlockPosition.b(i)), a(BlockPosition.c(i)), a(BlockPosition.d(i)));
+ return (((long) (int) (blockPos >> 42) & 4194303L) << 42) | (((long) (int) ((blockPos << 52) >> 56) & 1048575L)) | (((long) (int) ((blockPos << 26) >> 42) & 4194303L) << 20); // Simplify to reduce instruction count
}
public static long getZeroNode(long pos) {
@@ -201,15 +207,18 @@ public class SectionPos extends Vec3i {
return asLong(blockToSectionCoord(pos.getX()), blockToSectionCoord(pos.getY()), blockToSectionCoord(pos.getZ()));
}
+ // Paper start
+ public static long blockPosAsSectionLong(int i, int j, int k) {
+ return (((long) (i >> 4) & 4194303L) << 42) | (((long) (j >> 4) & 1048575L)) | (((long) (k >> 4) & 4194303L) << 20);
+ }
+ // Paper end
+
public static long asLong(int x, int y, int z) {
- long l = 0L;
- l |= ((long)x & 4194303L) << 42;
- l |= ((long)y & 1048575L) << 0;
- return l | ((long)z & 4194303L) << 20;
+ return (((long) x & 4194303L) << 42) | (((long) y & 1048575L)) | (((long) z & 4194303L) << 20); // Paper - Simplify to reduce instruction count
}
public long asLong() {
- return asLong(this.x(), this.y(), this.z());
+ return (((long) getX() & 4194303L) << 42) | (((long) getY() & 1048575L)) | (((long) getZ() & 4194303L) << 20); // Paper - Simplify to reduce instruction count
}
@Override
@@ -222,16 +231,11 @@ public class SectionPos extends Vec3i {
}
public static Stream<SectionPos> cube(SectionPos center, int radius) {
- int i = center.x();
- int j = center.y();
- int k = center.z();
- return betweenClosedStream(i - radius, j - radius, k - radius, i + radius, j + radius, k + radius);
+ return betweenClosedStream(center.getX() - radius, center.getY() - radius, center.getZ() - radius, center.getX() + radius, center.getY() + radius, center.getZ() + radius); // Paper - simplify/inline
}
public static Stream<SectionPos> aroundChunk(ChunkPos center, int radius, int minY, int maxY) {
- int i = center.x;
- int j = center.z;
- return betweenClosedStream(i - radius, minY, j - radius, i + radius, maxY - 1, j + radius);
+ return betweenClosedStream(center.x - radius, 0, center.z - radius, center.x + radius, 15, center.z + radius); // Paper - simplify/inline
}
public static Stream<SectionPos> betweenClosedStream(final int minX, final int minY, final int minZ, final int maxX, final int maxY, final int maxZ) {