Fix expected pod creations/deletions estimate in load test

test/e2e/scalability/load.go

@@ -320,12 +320,19 @@ var _ = SIGDescribe("Load capacity", func() {
 			// We would like to spread scaling replication controllers over time
 			// to make it possible to create/schedule & delete them in the meantime.
 			// Currently we assume that <throughput> pods/second average throughput.
-			// The expected number of created/deleted pods is less than totalPods/3.
-			scalingTime := time.Duration(totalPods/(3*throughput)) * time.Second
+
+			// The expected number of created/deleted pods is totalPods/4 when scaling
+			// for the first time, with each RC changing its size from X to a uniform
+			// random value in the interval [X/2, 3X/2].
+			scalingTime := time.Duration(totalPods/(4*throughput)) * time.Second
 			framework.Logf("Starting to scale %v objects first time...", itArg.kind)
 			scaleAllResources(configs, scalingTime, testPhaseDurations.StartPhase(300, "scaling first time"))
 			By("============================================================================")
 
+			// The expected number of created/deleted pods is totalPods/3 when scaling for
+			// the second time, with each RC changing its size from a uniform random value
+			// in the interval [X/2, 3X/2] to another uniform random value in same interval.
+			scalingTime = time.Duration(totalPods/(3*throughput)) * time.Second
 			framework.Logf("Starting to scale %v objects second time...", itArg.kind)
 			scaleAllResources(configs, scalingTime, testPhaseDurations.StartPhase(400, "scaling second time"))
 			By("============================================================================")