asim: export DefaultStartTime

This commit exports the simulator’s default start time, which will be used in
future commits to compare against scheduled event timestamps in the scheduler
package, ensuring timestamp is printed only when not at the start time.

Author: wenyihu6

pkg/kv/kvserver/asim/config/settings.go

@@ -33,10 +33,10 @@ const (
 )
 
 var (
-	// defaultStartTime is used as the default beginning time for simulation
+	// DefaultStartTime is used as the default beginning time for simulation
 	// runs. It isn't necessarily meaningful other than for logging and having
 	// "some" start time for components taking a time.Time.
-	defaultStartTime = time.Date(2022, 03, 21, 11, 0, 0, 0, time.UTC)
+	DefaultStartTime = time.Date(2022, 03, 21, 11, 0, 0, 0, time.UTC)
 )
 
 // SimulationSettings controls
@@ -116,7 +116,7 @@ type SimulationSettings struct {
 // DefaultSimulationSettings returns a set of default settings for simulation.
 func DefaultSimulationSettings() *SimulationSettings {
 	return &SimulationSettings{
-		StartTime:               defaultStartTime,
+		StartTime:               DefaultStartTime,
 		TickInterval:            defaultTickInteval,
 		MetricsInterval:         defaultMetricsInterval,
 		Seed:                    defaultSeed,