OpenSource/PaperMC
OpenSource/PaperMC
1
0
Fork 0
mirror of https://github.com/PaperMC/Paper.git synced 2024-12-28 23:38:25 +01:00
Code Issues Projects Releases Packages Wiki Activity

Optimize Loaded Chunks Cache Lookups

Browse source 
Reduces number of instructions a chunk lookup does
when accessing the last chunk cache. This reduces amount of work and opcodes
and allows better inlining.

In lots of profiling comparisons, this optimization was able to reduce the
cost of repeated chunk lookups that hit the cache pretty significantly.
This commit is contained in:
Aikar 2021-01-09 18:09:09 -05:00
parent 442fa32443
commit 1105e1ec76
1 changed files with 31 additions and 30 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

61
Spigot-Server-Patches/MC-Utils.patch
View file

@ -2428,7 +2428,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
@Nullable
private Consumer<Chunk> v;
- private final ChunkCoordIntPair loc;
+ private final ChunkCoordIntPair loc; public final long coordinateKey; // Paper - cache coordinate key
+ private final ChunkCoordIntPair loc; public final long coordinateKey; public final int locX; public final int locZ; // Paper - cache coordinate key
private volatile boolean x;
public Chunk(World world, ChunkCoordIntPair chunkcoordintpair, BiomeStorage biomestorage) {
@ -2437,7 +2437,8 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
this.entitySlices = (List[]) (new List[16]); // Spigot
this.world = (WorldServer) world; // CraftBukkit - type
- this.loc = chunkcoordintpair;
+ this.loc = chunkcoordintpair; this.coordinateKey = MCUtil.getCoordinateKey(chunkcoordintpair); // Paper - cache coordinate key
+ this.locX = chunkcoordintpair.x; this.locZ = chunkcoordintpair.z; // Paper - reduce need for field look ups
+ this.loc = chunkcoordintpair; this.coordinateKey = ChunkCoordIntPair.pair(locX, locZ); // Paper - cache long key
this.i = chunkconverter;
HeightMap.Type[] aheightmap_type = HeightMap.Type.values();
int j = aheightmap_type.length;
@ -2777,13 +2778,8 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
+ final Long2ObjectOpenHashMap<Chunk> loadedChunkMap = new Long2ObjectOpenHashMap<>(8192, 0.5f);
+
+ private final Chunk[] lastLoadedChunks = new Chunk[4 * 4];
+ private final long[] lastLoadedChunkKeys = new long[4 * 4];
+
+ {
+ java.util.Arrays.fill(this.lastLoadedChunkKeys, MCUtil.INVALID_CHUNK_KEY);
+ }
+
+ private static int getCacheKey(int x, int z) {
+ private static int getChunkCacheKey(int x, int z) {
+ return x & 3 | ((z & 3) << 2);
+ }
+
@ -2797,12 +2793,9 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
+
+ // rewrite cache if we have to
+ // we do this since we also cache null chunks
+ int cacheKey = getCacheKey(chunk.getPos().x, chunk.getPos().z);
+ int cacheKey = getChunkCacheKey(chunk.locX, chunk.locZ);
+
+ long cachedKey = this.lastLoadedChunkKeys[cacheKey];
+ if (cachedKey == chunk.coordinateKey) {
+ this.lastLoadedChunks[cacheKey] = chunk;
+ }
+ this.lastLoadedChunks[cacheKey] = chunk;
+ }
+
+ void removeLoadedChunk(Chunk chunk) {
@ -2815,36 +2808,35 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
+
+ // rewrite cache if we have to
+ // we do this since we also cache null chunks
+ int cacheKey = getCacheKey(chunk.getPos().x, chunk.getPos().z);
+ int cacheKey = getChunkCacheKey(chunk.locX, chunk.locZ);
+
+ long cachedKey = this.lastLoadedChunkKeys[cacheKey];
+ if (cachedKey == chunk.coordinateKey) {
+ Chunk cachedChunk = this.lastLoadedChunks[cacheKey];
+ if (cachedChunk != null && cachedChunk.coordinateKey == chunk.coordinateKey) {
+ this.lastLoadedChunks[cacheKey] = null;
+ }
+ }
+
+ public Chunk getChunkAtIfLoadedMainThread(int x, int z) {
+ int cacheKey = getCacheKey(x, z);
+ long chunkKey = MCUtil.getCoordinateKey(x, z);
+ public final Chunk getChunkAtIfLoadedMainThread(int x, int z) {
+ int cacheKey = getChunkCacheKey(x, z);
+
+ long cachedKey = this.lastLoadedChunkKeys[cacheKey];
+ if (cachedKey == chunkKey) {
+ Chunk cachedChunk = this.lastLoadedChunks[cacheKey];
+ if (cachedChunk != null && cachedChunk.locX == x & cachedChunk.locZ == z) {
+ return this.lastLoadedChunks[cacheKey];
+ }
+
+ Chunk ret = this.loadedChunkMap.get(chunkKey);
+ long chunkKey = ChunkCoordIntPair.pair(x, z);
+
+ this.lastLoadedChunkKeys[cacheKey] = chunkKey;
+ this.lastLoadedChunks[cacheKey] = ret;
+
+ return ret;
+ cachedChunk = this.loadedChunkMap.get(chunkKey);
+ // Skipping a null check to avoid extra instructions to improve inline capability
+ this.lastLoadedChunks[cacheKey] = cachedChunk;
+ return cachedChunk;
+ }
+
+ public Chunk getChunkAtIfLoadedMainThreadNoCache(int x, int z) {
+ return this.loadedChunkMap.get(MCUtil.getCoordinateKey(x, z));
+ public final Chunk getChunkAtIfLoadedMainThreadNoCache(int x, int z) {
+ return this.loadedChunkMap.get(ChunkCoordIntPair.pair(x, z));
+ }
+
+ public Chunk getChunkAtMainThread(int x, int z) {
+ public final Chunk getChunkAtMainThread(int x, int z) {
+ Chunk ret = this.getChunkAtIfLoadedMainThread(x, z);
+ if (ret != null) {
+ return ret;
@ -2889,7 +2881,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
+ throw new IllegalStateException();
+ }
+ ChunkCoordIntPair chunkPos = new ChunkCoordIntPair(x, z);
+ Long identifier = Long.valueOf(this.chunkFutureAwaitCounter++);
+ Long identifier = this.chunkFutureAwaitCounter++;
+ this.chunkMapDistance.addTicketAtLevel(TicketType.FUTURE_AWAIT, chunkPos, ticketLevel, identifier);
+ this.tickDistanceManager();
+
@ -4487,6 +4479,15 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
Fluid fluid = this.getFluid(blockposition);
return this.setTypeAndData(blockposition, fluid.getBlockData(), 3 | (flag ? 64 : 0));
@@ -0,0 +0,0 @@ public abstract class World implements GeneratorAccess, AutoCloseable {
if (isOutsideWorld(blockposition)) {
return Blocks.VOID_AIR.getBlockData();
} else {
- Chunk chunk = this.getChunkAt(blockposition.getX() >> 4, blockposition.getZ() >> 4);
+ Chunk chunk = (Chunk) this.getChunkProvider().getChunkAt(blockposition.getX() >> 4, blockposition.getZ() >> 4, ChunkStatus.FULL, true); // Paper - manually inline to reduce hops and avoid unnecessary null check to reduce total byte code size, this should never return null and if it does we will see it the next line but the real stack trace will matter in the chunk engine
return chunk.getType(blockposition);
}
diff --git a/src/main/java/net/minecraft/server/WorldBorder.java b/src/main/java/net/minecraft/server/WorldBorder.java
index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
--- a/src/main/java/net/minecraft/server/WorldBorder.java