Alerting: Enable group-level rule evaluation jittering by default, remove feature toggle (#82212)

* remove jitter feature flag

* Add an out so users can manually disable jitter

* Pass in cfg

* Add TODO to remove knob in future

pkg/services/featuremgmt/registry.go

@@ -1265,18 +1265,6 @@ var (
 			FrontendOnly: true,
 			Created:      time.Date(2024, time.January, 12, 12, 0, 0, 0, time.UTC),
 		},
-		{
-			Name:              "jitterAlertRules",
-			Description:       "Distributes alert rule evaluations more evenly over time, by rule group",
-			FrontendOnly:      false,
-			Stage:             FeatureStageGeneralAvailability,
-			Owner:             grafanaAlertingSquad,
-			AllowSelfServe:    false,
-			HideFromDocs:      false,
-			HideFromAdminPage: false,
-			RequiresRestart:   true,
-			Created:           time.Date(2024, time.January, 17, 12, 0, 0, 0, time.UTC),
-		},
 		{
 			Name:              "jitterAlertRulesWithinGroups",
 			Description:       "Distributes alert rule evaluations more evenly over time, including spreading out rules within the same group",

pkg/services/featuremgmt/toggles_gen.csv

@@ -149,7 +149,6 @@ enablePluginsTracingByDefault,experimental,@grafana/plugins-platform-backend,202
 cloudRBACRoles,experimental,@grafana/identity-access-team,2024-01-10,false,true,false
 alertingQueryOptimization,GA,@grafana/alerting-squad,2024-01-10,false,false,false
 newFolderPicker,experimental,@grafana/grafana-frontend-platform,2024-01-12,false,false,true
-jitterAlertRules,GA,@grafana/alerting-squad,2024-01-17,false,true,false
 jitterAlertRulesWithinGroups,preview,@grafana/alerting-squad,2024-01-17,false,true,false
 onPremToCloudMigrations,experimental,@grafana/grafana-operator-experience-squad,2024-01-22,false,false,false
 alertingSaveStatePeriodic,privatePreview,@grafana/alerting-squad,2024-01-22,false,false,false

pkg/services/featuremgmt/toggles_gen.go

@@ -607,10 +607,6 @@ const (
 	// Enables the nested folder picker without having nested folders enabled
 	FlagNewFolderPicker = "newFolderPicker"
 
-	// FlagJitterAlertRules
-	// Distributes alert rule evaluations more evenly over time, by rule group
-	FlagJitterAlertRules = "jitterAlertRules"
-
 	// FlagJitterAlertRulesWithinGroups
 	// Distributes alert rule evaluations more evenly over time, including spreading out rules within the same group
 	FlagJitterAlertRulesWithinGroups = "jitterAlertRulesWithinGroups"

pkg/services/ngalert/ngalert.go

@@ -274,7 +274,7 @@ func (ng *AlertNG) init() error {
 		BaseInterval:         ng.Cfg.UnifiedAlerting.BaseInterval,
 		MinRuleInterval:      ng.Cfg.UnifiedAlerting.MinInterval,
 		DisableGrafanaFolder: ng.Cfg.UnifiedAlerting.ReservedLabels.IsReservedLabelDisabled(models.FolderTitleLabel),
-		JitterEvaluations:    schedule.JitterStrategyFrom(ng.FeatureToggles),
+		JitterEvaluations:    schedule.JitterStrategyFrom(ng.Cfg.UnifiedAlerting, ng.FeatureToggles),
 		AppURL:               appUrl,
 		EvaluatorFactory:     evalFactory,
 		RuleStore:            ng.store,

pkg/services/ngalert/schedule/jitter.go

@@ -7,6 +7,7 @@ import (
 	"github.com/grafana/grafana-plugin-sdk-go/data"
 	"github.com/grafana/grafana/pkg/services/featuremgmt"
 	ngmodels "github.com/grafana/grafana/pkg/services/ngalert/models"
+	"github.com/grafana/grafana/pkg/setting"
 )
 
 // JitterStrategy represents a modifier to alert rule timing that affects how evaluations are distributed.
@@ -19,14 +20,14 @@ const (
 )
 
 // JitterStrategyFrom returns the JitterStrategy indicated by the current Grafana feature toggles.
-func JitterStrategyFrom(toggles featuremgmt.FeatureToggles) JitterStrategy {
-	strategy := JitterNever
+func JitterStrategyFrom(cfg setting.UnifiedAlertingSettings, toggles featuremgmt.FeatureToggles) JitterStrategy {
+	strategy := JitterByGroup
+	if cfg.DisableJitter {
+		return JitterNever
+	}
 	if toggles == nil {
 		return strategy
 	}
-	if toggles.IsEnabledGlobally(featuremgmt.FlagJitterAlertRules) {
-		strategy = JitterByGroup
-	}
 	if toggles.IsEnabledGlobally(featuremgmt.FlagJitterAlertRulesWithinGroups) {
 		strategy = JitterByRule
 	}