diff --git a/pkg/driver/trace_driver.go b/pkg/driver/trace_driver.go
index 67fc7cf2..81ce8ef6 100644
--- a/pkg/driver/trace_driver.go
+++ b/pkg/driver/trace_driver.go
@@ -196,6 +196,8 @@ func (d *Driver) functionsDriver(list *list.List, announceFunctionDone *sync.Wai
 			break // end of experiment for this individual function driver
 		}
 
+		d.announceWarmupEnd(minuteIndex, &currentPhase)
+
 		iat := time.Duration(IAT[iatIndex]) * time.Microsecond
 
 		schedulingDelay := time.Since(startOfExperiment).Microseconds() - previousIATSum
@@ -236,8 +238,6 @@ func (d *Driver) functionsDriver(list *list.List, announceFunctionDone *sync.Wai
 
 		iatIndex++
 
-		d.announceWarmupEnd(startOfExperiment, &currentPhase)
-
 		// counter updates
 		invocationSinceTheBeginningOfMinute++
 		if iatIndex > minuteIndexEnd {
@@ -257,8 +257,8 @@ func (d *Driver) functionsDriver(list *list.List, announceFunctionDone *sync.Wai
 	atomic.AddInt64(totalIssued, int64(iatIndex))
 }
 
-func (d *Driver) announceWarmupEnd(start time.Time, currentPhase *common.ExperimentPhase) {
-	if *currentPhase == common.WarmupPhase && hasMinuteExpired(start) {
+func (d *Driver) announceWarmupEnd(minuteIndex int, currentPhase *common.ExperimentPhase) {
+	if *currentPhase == common.WarmupPhase && minuteIndex >= d.Configuration.LoaderConfiguration.WarmupDuration {
 		*currentPhase = common.ExecutionPhase
 		log.Infof("Warmup phase has finished. Starting the execution phase.")
 	}
diff --git a/pkg/driver/trace_driver_test.go b/pkg/driver/trace_driver_test.go
index 8d224f64..1e0195b3 100644
--- a/pkg/driver/trace_driver_test.go
+++ b/pkg/driver/trace_driver_test.go
@@ -392,7 +392,11 @@ func TestDriverCompletely(t *testing.T) {
 			driver := createTestDriver(test.invocationStats)
 
 			if test.withWarmup {
-				driver.Configuration.LoaderConfiguration.WarmupDuration = 1
+				if test.traceGranularity == common.MinuteGranularity {
+					driver.Configuration.LoaderConfiguration.WarmupDuration = 1
+				} else {
+					driver.Configuration.LoaderConfiguration.WarmupDuration = 60
+				}
 			}
 			driver.Configuration.TraceDuration = test.experimentDurationMin
 			driver.Configuration.TraceGranularity = test.traceGranularity