Fix Spigot bug with chunk unloading

Spigot inserted their Slack Activity Accountant in the wrong location
resulting in a chunk being removed from the unload queue, inserted into
the unload map, but never calling the function to finish the removal....

This caused the chunk to become stuck in the unload map if ever hit, because
the unload map was meant to be a TEMPORARY location while it was saving.

Fix this by abort iteration AFTER the current chunk is finisehd processing

Also, improve how aggressive we are at unloading chunks, targetting 10% per tick instead.
These saves are asynchronous so there should be less of a hit here.

Spigot-Server-Patches/0390-Asynchronous-chunk-IO-and-loading.patch

@@ -3107,7 +3107,7 @@ index 52ea4f05a0c7f29f62f31bb032a5ceb905107e60..0f1576effe10795bcb8ed3b519f4dbaf
                  completablefuture = (CompletableFuture) this.statusFutures.get(i);
                  if (completablefuture != null) {
 diff --git a/src/main/java/net/minecraft/server/PlayerChunkMap.java b/src/main/java/net/minecraft/server/PlayerChunkMap.java
-index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714eeb236bbfa 100644
+index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..71ab7537313bbaf29f13ba3fae45bfb8a501429a 100644
 --- a/src/main/java/net/minecraft/server/PlayerChunkMap.java
 +++ b/src/main/java/net/minecraft/server/PlayerChunkMap.java
 @@ -63,7 +63,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
@@ -3164,7 +3164,13 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
              PlayerChunkMap.LOGGER.info("ThreadedAnvilChunkStorage ({}): All chunks are saved", this.w.getName());
          } else {
              this.visibleChunks.values().stream().filter(PlayerChunk::hasBeenLoaded).forEach((playerchunk) -> {
-@@ -437,11 +439,15 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -432,16 +434,20 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+ 
+     }
+ 
+-    private static final double UNLOAD_QUEUE_RESIZE_FACTOR = 0.96; // Spigot
++    private static final double UNLOAD_QUEUE_RESIZE_FACTOR = 0.90; // Spigot // Paper - unload more
+ 
      protected void unloadChunks(BooleanSupplier booleansupplier) {
          GameProfilerFiller gameprofilerfiller = this.world.getMethodProfiler();
  
@@ -3180,7 +3186,22 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
          }
  
          gameprofilerfiller.exit();
-@@ -481,6 +487,60 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -462,12 +468,13 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+             if (playerchunk != null) {
+                 this.pendingUnload.put(j, playerchunk);
+                 this.updatingChunksModified = true;
++                this.a(j, playerchunk); // Paper - Move up - don't leak chunks
+                 // Spigot start
+                 if (!booleansupplier.getAsBoolean() && this.unloadQueue.size() <= targetSize && activityAccountant.activityTimeIsExhausted()) {
+                     break;
+                 }
+                 // Spigot end
+-                this.a(j, playerchunk);
++                //this.a(j, playerchunk); // Paper - move up because spigot did a dumb
+             }
+         }
+         activityAccountant.endActivity(); // Spigot
+@@ -481,6 +488,60 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
  
      }
  
@@ -3241,7 +3262,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      private void a(long i, PlayerChunk playerchunk) {
          CompletableFuture<IChunkAccess> completablefuture = playerchunk.getChunkSave();
          Consumer<IChunkAccess> consumer = (ichunkaccess) -> { // CraftBukkit - decompile error
-@@ -494,7 +554,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -494,7 +555,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
                          ((Chunk) ichunkaccess).setLoaded(false);
                      }
  
@@ -3250,7 +3271,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
                      if (this.loadedChunks.remove(i) && ichunkaccess instanceof Chunk) {
                          Chunk chunk = (Chunk) ichunkaccess;
  
-@@ -502,6 +562,13 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -502,6 +563,13 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
                      }
                      this.autoSaveQueue.remove(playerchunk); // Paper
  
@@ -3264,7 +3285,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
                      this.lightEngine.a(ichunkaccess.getPos());
                      this.lightEngine.queueUpdate();
                      this.worldLoadListener.a(ichunkaccess.getPos(), (ChunkStatus) null);
-@@ -571,27 +638,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -571,27 +639,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
          }
      }
  
@@ -3313,7 +3334,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
              } catch (ReportedException reportedexception) {
                  Throwable throwable = reportedexception.getCause();
  
-@@ -605,7 +677,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -605,7 +678,32 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
              }
  
              return Either.left(new ProtoChunk(chunkcoordintpair, ChunkConverter.a, this.world)); // Paper - Anti-Xray - Add parameter
@@ -3347,7 +3368,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      }
  
      private CompletableFuture<Either<IChunkAccess, PlayerChunk.Failure>> b(PlayerChunk playerchunk, ChunkStatus chunkstatus) {
-@@ -823,18 +920,43 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -823,18 +921,43 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
          return this.u.get();
      }
  
@@ -3399,7 +3420,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
  
              ichunkaccess.setLastSaved(this.world.getTime());
              ichunkaccess.setNeedsSaving(false);
-@@ -845,28 +967,35 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -845,28 +968,35 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
                  NBTTagCompound nbttagcompound;
  
                  if (chunkstatus.getType() != ChunkStatus.Type.LEVELCHUNK) {
@@ -3437,7 +3458,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      }
  
      protected void setViewDistance(int i) {
-@@ -970,6 +1099,42 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -970,6 +1100,42 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
          }
      }
  
@@ -3480,7 +3501,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      @Nullable
      public NBTTagCompound readChunkData(ChunkCoordIntPair chunkcoordintpair) throws IOException { // Paper - private -> public
          NBTTagCompound nbttagcompound = this.read(chunkcoordintpair);
-@@ -992,33 +1157,55 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -992,33 +1158,55 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
  
      // Paper start - chunk status cache "api"
      public ChunkStatus getChunkStatusOnDiskIfCached(ChunkCoordIntPair chunkPos) {
@@ -3547,7 +3568,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      }
  
      public IChunkAccess getUnloadingChunk(int chunkX, int chunkZ) {
-@@ -1027,6 +1214,39 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -1027,6 +1215,39 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
      }
      // Paper end
  
@@ -3587,7 +3608,7 @@ index 94b0c54d9d4d77b724087be55ffe6ce464a0bbe7..963ce3eeec6f9eea087054ea48b714ee
      boolean isOutsideOfRange(ChunkCoordIntPair chunkcoordintpair) {
          // Spigot start
          return isOutsideOfRange(chunkcoordintpair, false);
-@@ -1374,6 +1594,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
+@@ -1374,6 +1595,7 @@ public class PlayerChunkMap extends IChunkLoader implements PlayerChunk.d {
  
      }