Started work on PathfinderCache - this will store paths that have been already calculated for later use. When a path becomes possibly invalidated, it is removed from the cache.

src/main/java/mekanism/common/Mekanism.java

@@ -61,6 +61,7 @@ import mekanism.common.tile.TileEntityElectricBlock;
 import mekanism.common.tile.TileEntityEnergizedSmelter;
 import mekanism.common.tile.TileEntitySalinationBlock;
 import mekanism.common.tile.TileEntitySalinationValve;
+import mekanism.common.transporter.PathfinderCache;
 import mekanism.common.transporter.TransporterManager;
 import mekanism.common.util.MekanismUtils;
 import mekanism.common.util.MekanismUtils.ResourceType;
@@ -983,8 +984,10 @@ public class Mekanism
 		activeVibrators.clear();
 		worldTickHandler.resetRegenChunks();
 		
+		//Reset consistent managers
 		MultiblockManager.reset();
-		TransporterManager.flowingStacks.clear();
+		TransporterManager.reset();
+		PathfinderCache.reset();
 	}
 	
 	@EventHandler

src/main/java/mekanism/common/transporter/PathfinderCache.java

@@ -0,0 +1,66 @@
+package mekanism.common.transporter;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import mekanism.api.Coord4D;
+
+public class PathfinderCache 
+{
+	public static Map<PathData, List<Coord4D>> cachedPaths = new HashMap<PathData, List<Coord4D>>();
+	
+	public static void onChanged(Coord4D location)
+	{
+		Set<PathData> toKill = new HashSet<PathData>();
+		
+		for(Map.Entry<PathData, List<Coord4D>> entry : cachedPaths.entrySet())
+		{
+			if(entry.getValue().contains(entry))
+			{
+				toKill.add(entry.getKey());
+			}
+		}
+		
+		for(PathData path : toKill)
+		{
+			cachedPaths.remove(path);
+		}
+	}
+	
+	public static void reset()
+	{
+		cachedPaths.clear();
+	}
+	
+	public static class PathData
+	{
+		public Coord4D start;
+		public Coord4D end;
+		
+		public PathData(Coord4D s, Coord4D e)
+		{
+			start = s;
+			end = e;
+		}
+		
+		@Override
+		public boolean equals(Object obj)
+		{
+			return obj instanceof PathData &&
+					((PathData)obj).start.equals(start) &&
+					((PathData)obj).end.equals(end);
+		}
+
+		@Override
+		public int hashCode()
+		{
+			int code = 1;
+			code = 31 * code + start.hashCode();
+			code = 31 * code + end.hashCode();
+			return code;
+		}
+	}
+}

src/main/java/mekanism/common/transporter/TransporterManager.java

@@ -24,6 +24,11 @@ import powercrystals.minefactoryreloaded.api.IDeepStorageUnit;
 public class TransporterManager
 {
 	public static Set<TransporterStack> flowingStacks = new HashSet<TransporterStack>();
+	
+	public static void reset()
+	{
+		flowingStacks.clear();
+	}
 
 	public static void add(TransporterStack stack)
 	{