diff --git a/graphx/src/main/scala/org/apache/spark/graphx/util/GraphGenerators.scala b/graphx/src/main/scala/org/apache/spark/graphx/util/GraphGenerators.scala
index 8a13c74221546..919c87839fcd9 100644
--- a/graphx/src/main/scala/org/apache/spark/graphx/util/GraphGenerators.scala
+++ b/graphx/src/main/scala/org/apache/spark/graphx/util/GraphGenerators.scala
@@ -114,13 +114,15 @@ object GraphGenerators {
     // Z ~ N(0, 1)
     var X: Double = maxVal
 
-    while (X >= maxVal) {
+    while (round(X) >= maxVal) {
       val Z = rand.nextGaussian()
       X = math.exp(mu + sigma*Z)
     }
-    math.floor(X).toInt
+    round(X)
   }
 
+  private def round(x: Double): Int = math.round(x.toFloat)
+
   /**
    * A random graph generator using the R-MAT model, proposed in
    * "R-MAT: A Recursive Model for Graph Mining" by Chakrabarti et al.