From 526961f2984aae1671a90cb830e816fc813d1602 Mon Sep 17 00:00:00 2001
From: Yuriy Tseretyan <tceretian@gmail.com>
Date: Thu, 30 Sep 2021 15:07:56 -0400
Subject: [PATCH] Alerting: rule evaluation loop to not access multiorg
 Alertmanager if no alerts to add (#39872)

---
 pkg/services/ngalert/schedule/schedule.go | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/pkg/services/ngalert/schedule/schedule.go b/pkg/services/ngalert/schedule/schedule.go
index 786a6328c70..0a40e485a99 100644
--- a/pkg/services/ngalert/schedule/schedule.go
+++ b/pkg/services/ngalert/schedule/schedule.go
@@ -478,6 +478,11 @@ func (sch *schedule) ruleRoutine(grafanaCtx context.Context, key models.AlertRul
 				sch.saveAlertStates(processedStates)
 				alerts := FromAlertStateToPostableAlerts(processedStates, sch.stateManager, sch.appURL)
 
+				if len(alerts.PostableAlerts) == 0 {
+					sch.log.Debug("no alerts to put in the notifier", "org", alertRule.OrgID)
+					return nil
+				}
+
 				sch.log.Debug("sending alerts to notifier", "count", len(alerts.PostableAlerts), "alerts", alerts.PostableAlerts, "org", alertRule.OrgID)
 				n, err := sch.multiOrgNotifier.AlertmanagerFor(alertRule.OrgID)
 				if err == nil {