Making GCInterval Configurable

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changelog
 
 ## master / unreleased
+* [FEATURE] Added the flag `-alertmanager.alerts-gc-interval` to configure alert manager alerts Garbage collection interval. #5550
 * [FEATURE] Ruler: Add support for Limit field on RuleGroup. #5528
 * [FEATURE] AlertManager: Add support for Webex, Discord and Telegram Receiver. #5493
 * [FEATURE] Ingester: added `-admin-limit-message` to customize the message contained in limit errors.#5460

docs/configuration/config-file-reference.md

@@ -433,6 +433,10 @@ cluster:
 # CLI flag: -alertmanager.api-concurrency
 [api_concurrency: <int> | default = 0]
 
+# Alertmanager alerts Garbage collection interval.
+# CLI flag: -alertmanager.alerts-gc-interval
+[gc_interval: <duration> | default = 30m]
+
 alertmanager_client:
   # Timeout for downstream alertmanagers.
   # CLI flag: -alertmanager.alertmanager-client.remote-timeout

pkg/alertmanager/alertmanager.go

@@ -85,6 +85,7 @@ type Config struct {
 	Store             alertstore.AlertStore
 	PersisterConfig   PersisterConfig
 	APIConcurrency    int
+	GCInterval        time.Duration
 }
 
 // An Alertmanager manages the alerts for one user.
@@ -254,8 +255,7 @@ func New(cfg *Config, reg *prometheus.Registry) (*Alertmanager, error) {
 	if am.cfg.Limits != nil {
 		callback = newAlertsLimiter(am.cfg.UserID, am.cfg.Limits, reg)
 	}
-
-	am.alerts, err = mem.NewAlerts(context.Background(), am.marker, 30*time.Minute, callback, am.logger, am.registry)
+	am.alerts, err = mem.NewAlerts(context.Background(), am.marker, am.cfg.GCInterval, callback, am.logger, am.registry)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create alerts: %v", err)
 	}

pkg/alertmanager/alertmanager_test.go

@@ -46,6 +46,7 @@ func createAlertmanagerAndSendAlerts(t *testing.T, alertGroups, groupsLimit, exp
 		TenantDataDir:   t.TempDir(),
 		ExternalURL:     &url.URL{Path: "/am"},
 		ShardingEnabled: false,
+		GCInterval:      30 * time.Minute,
 	}, reg)
 	require.NoError(t, err)
 	defer am.StopAndWait()

pkg/alertmanager/multitenant.go

@@ -78,8 +78,9 @@ type MultitenantAlertmanagerConfig struct {
 
 	Cluster ClusterConfig `yaml:"cluster"`
 
-	EnableAPI      bool `yaml:"enable_api"`
-	APIConcurrency int  `yaml:"api_concurrency"`
+	EnableAPI      bool          `yaml:"enable_api"`
+	APIConcurrency int           `yaml:"api_concurrency"`
+	GCInterval     time.Duration `yaml:"gc_interval"`
 
 	// For distributor.
 	AlertmanagerClient ClientConfig `yaml:"alertmanager_client"`
@@ -119,7 +120,7 @@ func (cfg *MultitenantAlertmanagerConfig) RegisterFlags(f *flag.FlagSet) {
 
 	f.BoolVar(&cfg.EnableAPI, "experimental.alertmanager.enable-api", false, "Enable the experimental alertmanager config api.")
 	f.IntVar(&cfg.APIConcurrency, "alertmanager.api-concurrency", 0, "Maximum number of concurrent GET API requests before returning an error.")
-
+	f.DurationVar(&cfg.GCInterval, "alertmanager.alerts-gc-interval", 30*time.Minute, "Alertmanager alerts Garbage collection interval.")
 	f.BoolVar(&cfg.ShardingEnabled, "alertmanager.sharding-enabled", false, "Shard tenants across multiple alertmanager instances.")
 	f.Var(&cfg.EnabledTenants, "alertmanager.enabled-tenants", "Comma separated list of tenants whose alerts this alertmanager can process. If specified, only these tenants will be handled by alertmanager, otherwise this alertmanager can process alerts from all tenants.")
 	f.Var(&cfg.DisabledTenants, "alertmanager.disabled-tenants", "Comma separated list of tenants whose alerts this alertmanager cannot process. If specified, a alertmanager that would normally pick the specified tenant(s) for processing will ignore them instead.")
@@ -969,6 +970,7 @@ func (am *MultitenantAlertmanager) newAlertmanager(userID string, amConfig *amco
 		PersisterConfig:   am.cfg.Persister,
 		Limits:            am.limits,
 		APIConcurrency:    am.cfg.APIConcurrency,
+		GCInterval:        am.cfg.GCInterval,
 	}, reg)
 	if err != nil {
 		return nil, fmt.Errorf("unable to start Alertmanager for user %v: %v", userID, err)

pkg/alertmanager/multitenant_test.go

@@ -83,7 +83,7 @@ func mockAlertmanagerConfig(t *testing.T) *MultitenantAlertmanagerConfig {
 	cfg.ShardingRing.InstanceAddr = "127.0.0.1"
 	cfg.PollInterval = time.Minute
 	cfg.ShardingRing.FinalSleep = 0
-
+	cfg.GCInterval = 30 * time.Minute
 	return cfg
 }