diff --git a/src/pocketmine/level/format/anvil/Chunk.php b/src/pocketmine/level/format/anvil/Chunk.php
index c9bd003e7..221dc3128 100644
--- a/src/pocketmine/level/format/anvil/Chunk.php
+++ b/src/pocketmine/level/format/anvil/Chunk.php
@@ -160,6 +160,9 @@ class Chunk extends BaseChunk{
 		$nbt->Sections = new Enum("Sections", []);
 		$nbt->Sections->setTagType(NBT::TAG_Compound);
 		foreach($this->getSections() as $section){
+			if($section instanceof EmptyChunkSection){
+				continue;
+			}
 			$nbt->Sections[$section->getY()] = new Compound(null, [
 				"Y" => new Byte("Y", $section->getY()),
 				"Blocks" => new ByteArray("Blocks", $section->getIdArray()),
diff --git a/src/pocketmine/level/format/mcregion/Chunk.php b/src/pocketmine/level/format/mcregion/Chunk.php
index 0463ac361..effdaed3a 100644
--- a/src/pocketmine/level/format/mcregion/Chunk.php
+++ b/src/pocketmine/level/format/mcregion/Chunk.php
@@ -70,6 +70,16 @@ class Chunk extends BaseFullChunk{
 			$this->nbt->BiomeColors = new IntArray("BiomeColors", array_fill(0, 156, Binary::readInt("\x00\x85\xb2\x4a")));
 		}
 
+		if(!isset($this->nbt->Blocks)){
+			$this->nbt->Blocks = new ByteArray("Blocks", str_repeat("\x00", 32768));
+		}
+
+		if(!isset($this->nbt->Data)){
+			$this->nbt->Data = new ByteArray("Data", $half = str_repeat("\x00", 16384));
+			$this->nbt->SkyLight = new ByteArray("SkyLight", $half);
+			$this->nbt->BlockLight = new ByteArray("BlockLight", $half);
+		}
+
 		parent::__construct($level, $this->nbt["xPos"], $this->nbt["zPos"], $this->nbt["Blocks"], $this->nbt["Data"], $this->nbt["SkyLight"], $this->nbt["BlockLight"], $this->nbt->Biomes->getValue(), $this->nbt->BiomeColors->getValue(), $this->nbt->Entities->getValue(), $this->nbt->TileEntities->getValue());
 		unset($this->nbt->Blocks);
 		unset($this->nbt->Data);
@@ -253,13 +263,15 @@ class Chunk extends BaseFullChunk{
 		$nbt->xPos = new Int("xPos", $this->x);
 		$nbt->zPos = new Int("zPos", $this->z);
 
-		$nbt->Blocks = new ByteArray("Blocks", $this->getBlockIdArray());
-		$nbt->Data = new ByteArray("Data", $this->getBlockDataArray());
-		$nbt->SkyLight = new ByteArray("SkyLight", $this->getBlockSkyLightArray());
-		$nbt->BlockLight = new ByteArray("BlockLight", $this->getBlockLightArray());
+		if($this->isGenerated()){
+			$nbt->Blocks = new ByteArray("Blocks", $this->getBlockIdArray());
+			$nbt->Data = new ByteArray("Data", $this->getBlockDataArray());
+			$nbt->SkyLight = new ByteArray("SkyLight", $this->getBlockSkyLightArray());
+			$nbt->BlockLight = new ByteArray("BlockLight", $this->getBlockLightArray());
 
-		$nbt->Biomes = new ByteArray("Biomes", $this->getBiomeIdArray());
-		$nbt->BiomeColors = new IntArray("BiomeColors", $this->getBiomeColorArray());
+			$nbt->Biomes = new ByteArray("Biomes", $this->getBiomeIdArray());
+			$nbt->BiomeColors = new IntArray("BiomeColors", $this->getBiomeColorArray());
+		}
 
 		$entities = [];
 
diff --git a/src/pocketmine/level/generator/GenerationManager.php b/src/pocketmine/level/generator/GenerationManager.php
index d945ad988..b94d8d9a2 100644
--- a/src/pocketmine/level/generator/GenerationManager.php
+++ b/src/pocketmine/level/generator/GenerationManager.php
@@ -144,12 +144,17 @@ class GenerationManager{
 			$this->levels[$levelID]->populateChunk($chunkX, $chunkZ); //Request population directly
 			if(isset($this->levels[$levelID])){
 				$this->generatedQueue[$levelID][$index] = true;
-				if(count($this->generatedQueue[$levelID]) > 6){
+				if(count($this->generatedQueue[$levelID]) > 2){
 					foreach($this->levels[$levelID]->getChangedChunks() as $chunk){
-						$this->sendChunk($levelID, $chunk);
+						if($chunk->isPopulated()){
+							$this->sendChunk($levelID, $chunk);
+						}
 					}
-					$this->levels[$levelID]->doGarbageCollection();
 					$this->levels[$levelID]->cleanChangedChunks();
+				}
+
+				if(count($this->generatedQueue[$levelID]) > 8){
+					$this->levels[$levelID]->doGarbageCollection();
 					$this->generatedQueue[$levelID] = [];
 				}
 			}