diff --git a/core/src/main/java/com/seibel/distanthorizons/core/level/DhServerLevel.java b/core/src/main/java/com/seibel/distanthorizons/core/level/DhServerLevel.java
index 91b1402ef..42328cd88 100644
--- a/core/src/main/java/com/seibel/distanthorizons/core/level/DhServerLevel.java
+++ b/core/src/main/java/com/seibel/distanthorizons/core/level/DhServerLevel.java
@@ -66,8 +66,8 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 	private final RemotePlayerConnectionHandler remotePlayerConnectionHandler;
 	
 	private final ConcurrentLinkedQueue<IServerPlayerWrapper> worldGenLoopingQueue = new ConcurrentLinkedQueue<>();
-	private final ConcurrentMap<Long, IncompleteDataSourceEntry> incompleteDataSources = new ConcurrentHashMap<>();
-	private final ConcurrentMap<Long, IncompleteDataSourceEntry> fullDataRequests = new ConcurrentHashMap<>();
+	private final ConcurrentMap<Long, DataSourceRequestGroup> requestGroupsByPos = new ConcurrentHashMap<>();
+	private final ConcurrentMap<Long, DataSourceRequestGroup> requestGroupsByFutureId = new ConcurrentHashMap<>();
 	
 	public DhServerLevel(AbstractSaveStructure saveStructure, IServerLevelWrapper serverLevelWrapper, RemotePlayerConnectionHandler remotePlayerConnectionHandler)
 	{
@@ -107,18 +107,18 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 				
 				while (true)
 				{
-					IncompleteDataSourceEntry entry = this.incompleteDataSources.computeIfAbsent(msg.sectionPos, pos ->
+					DataSourceRequestGroup requestGroup = this.requestGroupsByPos.computeIfAbsent(msg.sectionPos, pos ->
 					{
-						IncompleteDataSourceEntry newEntry = new IncompleteDataSourceEntry();
-						this.trySetGeneratedDataSourceToEntry(newEntry, pos);
-						return newEntry;
+						DataSourceRequestGroup newGroup = new DataSourceRequestGroup();
+						this.tryFulfillDataSourceRequestGroup(newGroup, pos);
+						return newGroup;
 					});
-					// If this fails, current entry is being drained and need to create another one
-					if (entry.requestCollectionSemaphore.tryAcquire())
+					// If this fails, current group is being drained and need to create another one
+					if (requestGroup.requestAddSemaphore.tryAcquire())
 					{
-						this.fullDataRequests.put(msg.futureId, entry);
-						entry.requestMessages.put(msg.futureId, msg);
-						entry.requestCollectionSemaphore.release();
+						this.requestGroupsByFutureId.put(msg.futureId, requestGroup);
+						requestGroup.requestMessages.put(msg.futureId, msg);
+						requestGroup.requestAddSemaphore.release();
 						break;
 					}
 				}
@@ -162,23 +162,30 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 		
 		serverPlayerState.session.registerHandler(CancelMessage.class, msg ->
 		{
-			IncompleteDataSourceEntry entry = this.fullDataRequests.remove(msg.futureId);
-			if (entry == null)
+			DataSourceRequestGroup requestGroup = this.requestGroupsByFutureId.remove(msg.futureId);
+			if (requestGroup == null)
 			{
 				return;
 			}
-			FullDataSourceRequestMessage requestMessage = entry.requestMessages.remove(msg.futureId);
+			FullDataSourceRequestMessage requestMessage = requestGroup.requestMessages.remove(msg.futureId);
 			
 			serverPlayerState.getRateLimiterSet(this).fullDataRequestConcurrencyLimiter.release();
 			
-			entry.requestCollectionSemaphore.acquireUninterruptibly(Short.MAX_VALUE);
-			if (entry.requestMessages.isEmpty())
+			if (requestGroup.requestRemoveSemaphore.tryAcquire())
 			{
-				this.incompleteDataSources.remove(requestMessage.sectionPos);
-				this.serverside.fullDataFileHandler.removeRetrievalRequestIf(pos -> pos == requestMessage.sectionPos);
+				// Prevent adding requests in case request will be removed by cancellation
+				requestGroup.requestAddSemaphore.acquireUninterruptibly(Short.MAX_VALUE);
+
+				if (requestGroup.requestMessages.isEmpty())
+				{
+					this.requestGroupsByPos.remove(requestMessage.sectionPos);
+					this.serverside.fullDataFileHandler.removeRetrievalRequestIf(pos -> pos == requestMessage.sectionPos);
+				}
+				else
+				{
+					requestGroup.requestAddSemaphore.release(Short.MAX_VALUE);
+				}
 			}
-			
-			entry.requestCollectionSemaphore.release(Short.MAX_VALUE);
 		});
 	}
 	
@@ -234,19 +241,20 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 		this.chunkToLodBuilder.tick();
 		
 		// Send finished data source requests
-		for (Map.Entry<Long, IncompleteDataSourceEntry> mapEntry : this.incompleteDataSources.entrySet())
+		for (Map.Entry<Long, DataSourceRequestGroup> entry : this.requestGroupsByPos.entrySet())
 		{
-			IncompleteDataSourceEntry entry = mapEntry.getValue();
+			DataSourceRequestGroup requestGroup = entry.getValue();
 			
-			if (entry.fullDataSource == null)
+			if (requestGroup.fullDataSource == null)
 			{
 				continue;
 			}
 			
-			this.incompleteDataSources.remove(mapEntry.getKey());
+			// Prevent adding or removing requests
+			requestGroup.requestRemoveSemaphore.acquireUninterruptibly(Short.MAX_VALUE);
+			requestGroup.requestAddSemaphore.acquireUninterruptibly(Short.MAX_VALUE);
 			
-			// This semaphore is intentionally acquired forever
-			entry.requestCollectionSemaphore.acquireUninterruptibly(Short.MAX_VALUE);
+			this.requestGroupsByPos.remove(entry.getKey());
 			
 			ThreadPoolExecutor executor = ThreadPoolUtil.getNetworkCompressionExecutor();
 			if (executor == null)
@@ -256,10 +264,10 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 			}
 			CompletableFuture.runAsync(() ->
 			{
-				FullDataSourceResponseMessage response = new FullDataSourceResponseMessage(entry.fullDataSource);
-				for (FullDataSourceRequestMessage msg : entry.requestMessages.values())
+				FullDataSourceResponseMessage response = new FullDataSourceResponseMessage(requestGroup.fullDataSource);
+				for (FullDataSourceRequestMessage msg : requestGroup.requestMessages.values())
 				{
-					this.fullDataRequests.remove(msg.futureId);
+					this.requestGroupsByFutureId.remove(msg.futureId);
 					
 					ServerPlayerState serverPlayerState = this.remotePlayerConnectionHandler.getConnectedPlayer(msg.serverPlayer());
 					if (serverPlayerState == null)
@@ -387,12 +395,12 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 	@Override
 	public boolean hasSkyLight() { return this.serverLevelWrapper.hasSkyLight(); }
 	
-	private void trySetGeneratedDataSourceToEntry(IncompleteDataSourceEntry entry, long pos)
+	private void tryFulfillDataSourceRequestGroup(DataSourceRequestGroup requestGroup, long pos)
 	{
 		this.serverside.fullDataFileHandler.getAsync(pos).thenAccept(fullDataSource -> {
 			if (this.serverside.fullDataFileHandler.isFullyGenerated(fullDataSource.columnGenerationSteps))
 			{
-				entry.fullDataSource = fullDataSource;
+				requestGroup.fullDataSource = fullDataSource;
 			}
 			else
 			{
@@ -404,10 +412,10 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 	@Override
 	public void onWorldGenTaskComplete(long pos)
 	{
-		IncompleteDataSourceEntry entry = this.incompleteDataSources.get(pos);
-		if (entry != null)
+		DataSourceRequestGroup requestGroup = this.requestGroupsByPos.get(pos);
+		if (requestGroup != null)
 		{
-			this.trySetGeneratedDataSourceToEntry(entry, pos);
+			this.tryFulfillDataSourceRequestGroup(requestGroup, pos);
 		}
 	}
 	
@@ -424,12 +432,15 @@ public class DhServerLevel extends AbstractDhLevel implements IDhServerLevel
 		messageList.add("["+dimName+"]");
 	}
 	
-	private static class IncompleteDataSourceEntry
+	private static class DataSourceRequestGroup
 	{
+		public final ConcurrentMap<Long, FullDataSourceRequestMessage> requestMessages = new ConcurrentHashMap<>();
+
 		@CheckForNull
 		public FullDataSourceV2 fullDataSource;
-		public final ConcurrentMap<Long, FullDataSourceRequestMessage> requestMessages = new ConcurrentHashMap<>();
-		public final Semaphore requestCollectionSemaphore = new Semaphore(Short.MAX_VALUE, true);
+		
+		public final Semaphore requestAddSemaphore = new Semaphore(Short.MAX_VALUE, true);
+		public final Semaphore requestRemoveSemaphore = new Semaphore(Short.MAX_VALUE, true);
 	}
 	
 }
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