Changed speed estimation and time remaining variables to Double instead of Int.

src/scala/spark/ShuffleTrackerStrategy.scala

@@ -151,7 +151,7 @@ extends ShuffleTrackerStrategy with Logging {
   private var hasBlocksPerInputSplit: Array[Array[Int]] = null
 
   // Stored in bytes per millisecond
-  private var speedPerInputSplit: Array[Array[Int]] = null
+  private var speedPerInputSplit: Array[Array[Double]] = null
   
   private var curConnectionsPerLoc: Array[Int] = null
   private var totalConnectionsPerLoc: Array[Int] = null
@@ -172,7 +172,7 @@ extends ShuffleTrackerStrategy with Logging {
     hasBlocksPerInputSplit = Array.tabulate(numReducers, numMappers)((_,_) => 0)
 
     // Initialize to -1
-    speedPerInputSplit = Array.tabulate(numReducers, numMappers)((_,_) => -1)
+    speedPerInputSplit = Array.tabulate(numReducers, numMappers)((_,_) => -1.0)
 
     curConnectionsPerLoc = Array.tabulate(numMappers)(_ => 0)
     totalConnectionsPerLoc = Array.tabulate(numMappers)(_ => 0)
@@ -183,22 +183,21 @@ extends ShuffleTrackerStrategy with Logging {
 
     // Estimate time remaining to finish receiving for all reducer/mapper pairs
     // If speed is unknown or zero then make it 1 to give a large estimate
-    var individualEstimates = Array.tabulate(numReducers, numMappers)((_,_) => 0)
+    var individualEstimates = Array.tabulate(numReducers, numMappers)((_,_) => 0.0)
     for (i <- 0 until numReducers; j <- 0 until numMappers) {
       var blocksRemaining = totalBlocksPerInputSplit(i)(j) - 
         hasBlocksPerInputSplit(i)(j)
       assert(blocksRemaining >= 0)
       
       individualEstimates(i)(j) = 
-        { if (blocksRemaining < 0) 0 else blocksRemaining } * 
-        Shuffle.BlockSize / 
-        { if (speedPerInputSplit(i)(j) <= 0) 1 else speedPerInputSplit(i)(j) }
+        1.0 * blocksRemaining * Shuffle.BlockSize / 
+        { if (speedPerInputSplit(i)(j) <= 0.0) 1.0 else speedPerInputSplit(i)(j) }
     }
     
-    // Check if all individualEstimates entries have non-zero values
+    // Check if all speedPerInputSplit entries have non-zero values
     var estimationComplete = true
     for (i <- 0 until numReducers; j <- 0 until numMappers) {
-      if (speedPerInputSplit(i)(j) < 0) {
+      if (speedPerInputSplit(i)(j) < 0.0) {
         estimationComplete = false
       }
     }  
@@ -285,7 +284,7 @@ extends ShuffleTrackerStrategy with Logging {
     // TODO: We are forgetting the old speed. Can use averaging at some point.
     if (receptionStat.bytesReceived > 0) {
       speedPerInputSplit(reducerSplitInfo.splitId)(receptionStat.serverSplitIndex) = 
-        receptionStat.bytesReceived / (receptionStat.timeSpent + 1)
+        1.0 * receptionStat.bytesReceived / (receptionStat.timeSpent + 1.0)
     }
     
     // Update current connections to the mapper