Trying to tick everything is slow.

- Keep track of tickable instances separately.

src/main/java/com/simibubi/create/content/logistics/block/belts/tunnel/BeltTunnelInstance.java

@@ -16,7 +16,7 @@ import java.util.Collection;
 import java.util.EnumMap;
 import java.util.Map;
 
-public class BeltTunnelInstance extends TileEntityInstance<BeltTunnelTileEntity> {
+public class BeltTunnelInstance extends TileEntityInstance<BeltTunnelTileEntity> implements ITickableInstance {
     public static void register(TileEntityType<? extends BeltTunnelTileEntity> type) {
         DistExecutor.unsafeRunWhenOn(Dist.CLIENT, () -> () ->
                 InstancedTileRenderRegistry.instance.register(type, BeltTunnelInstance::new));

src/main/java/com/simibubi/create/content/logistics/block/funnel/FunnelInstance.java

@@ -13,7 +13,7 @@ import net.minecraftforge.fml.DistExecutor;
 
 import java.util.ArrayList;
 
-public class FunnelInstance extends TileEntityInstance<FunnelTileEntity> {
+public class FunnelInstance extends TileEntityInstance<FunnelTileEntity> implements ITickableInstance {
     public static void register(TileEntityType<? extends FunnelTileEntity> type) {
         DistExecutor.unsafeRunWhenOn(Dist.CLIENT, () -> () ->
                 InstancedTileRenderRegistry.instance.register(type, FunnelInstance::new));

src/main/java/com/simibubi/create/foundation/render/backend/instancing/ITickableInstance.java

@@ -0,0 +1,8 @@
+package com.simibubi.create.foundation.render.backend.instancing;
+
+public interface ITickableInstance {
+    /**
+     * Called every frame, this can be used to make more dynamic animations.
+     */
+    void tick();
+}

src/main/java/com/simibubi/create/foundation/render/backend/instancing/InstancedTileRenderer.java

@@ -1,7 +1,6 @@
 package com.simibubi.create.foundation.render.backend.instancing;
 
-import java.util.HashMap;
+import java.util.*;
-import java.util.Map;
 
 import javax.annotation.Nullable;
 
@@ -20,6 +19,8 @@ import net.minecraft.world.World;
 public abstract class InstancedTileRenderer<P extends BasicProgram> {
     protected Map<TileEntity, TileEntityInstance<?>> instances = new HashMap<>();
 
+    protected Map<TileEntity, ITickableInstance> tickableInstances = new HashMap<>();
+
     protected Map<MaterialType<?>, RenderMaterial<P, ?>> materials = new HashMap<>();
 
     protected InstancedTileRenderer() {
@@ -41,7 +42,7 @@ public abstract class InstancedTileRenderer<P extends BasicProgram> {
     }
 
     public void beginFrame(double cameraX, double cameraY, double cameraZ) {
-        instances.values().forEach(TileEntityInstance::tick);
+        tickableInstances.values().forEach(ITickableInstance::tick);
     }
 
     public void render(RenderType layer, Matrix4f viewProjection, double camX, double camY, double camZ) {
@@ -79,6 +80,9 @@ public abstract class InstancedTileRenderer<P extends BasicProgram> {
 
             if (renderer != null) {
                 instances.put(tile, renderer);
+
+                if (renderer instanceof ITickableInstance)
+                    tickableInstances.put(tile, (ITickableInstance) renderer);
             }
 
             return renderer;
@@ -126,6 +130,7 @@ public abstract class InstancedTileRenderer<P extends BasicProgram> {
             if (instance != null) {
                 instance.remove();
                 instances.remove(tile);
+                tickableInstances.remove(tile);
             }
         }
     }

src/main/java/com/simibubi/create/foundation/render/backend/instancing/TileEntityInstance.java

@@ -33,11 +33,6 @@ public abstract class TileEntityInstance<T extends TileEntity> {
         }
     }
 
-    /**
-     * Called every frame, this can be used to make more dynamic animations.
-     */
-    public void tick() { }
-
     /**
      * Acquire all {@link InstanceKey}s and initialize any data you may need to calculate the instance properties.
      */