admin: stop the maintenance scanner pinning itself to one scan per second after a transient failure (#10887)

* admin: honour persisted task configs when building the maintenance policy buildPolicyFromTaskConfigs passed a literal nil to vacuum, erasure_coding and balance LoadConfigFromPersistence. Those functions look for their LoadXTaskPolicy() accessor via a type assertion, which a nil interface can never satisfy, so every call fell through to NewDefaultConfig() and the policy came back with the compiled-in defaults - Enabled: true among them. A task disabled on disk was therefore still scheduled, and the only trace was a glog.V(1) "Using default ... configuration" line. Thread the real ConfigPersistence through instead. There are two copies of this function: the one in weed/admin/dash builds config.Policy on the normal admin startup path and can simply take cp as its receiver, and the one in weed/admin/maintenance is the fallback used when the config carries no policy yet, which now receives the store from NewMaintenanceManager. weed/admin/dash already imports weed/admin/maintenance, so the maintenance side has to keep the duck-typed interface{} parameter that the task loaders already use rather than importing the concrete type back. The store is only handed over when a data directory is configured: an unconfigured one has nothing to read, and a typed nil pointer would pass the loaders' type assertion and then panic on first use. Fixes #10874 * admin: restore the maintenance scan cadence after an error backoff scanLoop shortens its ticker to the error backoff delay after a failed scan, but it decided whether to replace the ticker by comparing the target interval against the configured scan interval instead of against the interval the ticker was actually running at. Once the errors stopped, getScanInterval returned the configured interval again, the comparison came out false, and the ticker was left at the backoff delay - so a single transient scan failure pinned the scanner to one scan per second for the rest of the process lifetime. That is the ~1/second cadence in issue #10874: 658 KB/s of "Cancelled N stale pending balance tasks before re-detection" and 193k orphaned task files over two days. Track the interval the ticker is running at and compare against that, so both entering the backoff and returning to the normal cadence replace the ticker. While in here: - defer ticker.Stop() bound the ticker that was current when the defer was registered, so every replacement ticker leaked on return. Wrap it in a closure. - running was written by Start/Stop and read by all three background loops without synchronisation. Guard it with the existing mutex, fold the running check in triggerScanInternal into the lock it already takes, and make Stop a no-op when not running so a second call cannot close the stop channel twice. Refs #10874 * admin: make the maintenance policy actually reach the task detectors Loading the persisted task configs into the maintenance policy only matters if something reads that policy, and nothing did. MaintenanceIntegration pushes the policy into every registered detector and scheduler through interface{ SetEnabled(bool) } and interface{ SetMaxConcurrent(int) } type assertions. Every task registered through base.RegisterTask is backed by base.GenericDetector and base.GenericScheduler, and neither implemented either method, so all four assertions failed silently for every task on every startup. The policy's enabled flag reached nothing: ScanWithTaskDetectors gates on detector.IsEnabled(), and the queue's policy lookups for max concurrent and repeat interval are fallbacks that only fire when the scheduler reports zero, which the generic scheduler never does. Add the setters, delegating to the TaskConfig.SetEnabled the interface already declares and to TaskDefinition.MaxConcurrent, which is what GetMaxConcurrent returns. Applying the policy required three more fixes, because with the assertions working the policy could now do damage as well as good: - IsTaskEnabled reports false for a task type the policy has no entry for, so applying it unconditionally would have disabled every task the policy does not list. Skip task types with no policy entry: no entry means no opinion, not disabled. - ec_balance was exactly such a task. It is registered like the other three but had no entry in the policy builder and no accessor on ConfigPersistence at all, so its configuration could never be persisted. Add SaveEcBalanceTaskPolicy/LoadEcBalanceTaskPolicy, the task_ec_balance.pb file, the SaveTaskPolicy dispatcher case, and the policy entry. - InitMaintenanceManager ran before loadTaskConfigurationsFromPersistence, which replaces each task's whole config object, so the policy was applied and then immediately thrown away. Swap the order. Both read the same files, so the policy is now the last writer and stays authoritative. MaintenanceManager.UpdateConfig also updated the queue's and the scanner's policy but not the integration's, so a policy changed at runtime never reached the detectors. Add MaintenanceIntegration.SetPolicy and call it. While building the policy, stop hand-copying each task's fields and use the task's own ToTaskPolicy(). The hand-written version was a second definition of every task's policy and had already lost the erasure coding preferred tags and replica placement and the balance IO rate limit. For the same reason, the "nothing persisted yet" branches of LoadVacuumTaskPolicy, LoadErasureCodingTaskPolicy and LoadBalanceTaskPolicy now derive from each task's NewDefaultConfig() instead of a third hand-written copy. Those copies had drifted, so with a data directory but no config file on disk the effective defaults differed from what the task and the admin UI schema both advertise: vacuum scan interval 24h -> 2h balance scan interval 6h -> 30m balance imbalance 0.1 -> 0.2 erasure coding scan interval 168h -> 1h erasure coding fullness 0.90 -> 0.95 erasure coding min volume 1024MB -> 30MB Finally, weed/admin/dash and weed/admin/maintenance each carried a copy of the policy builder and they had already diverged. Export the maintenance one as BuildPolicyFromTaskConfigs and have dash call it. Refs #10874 * worker: warn when a config store cannot supply a task's persisted config LoadConfigFromPersistence logged a single glog.V(1) "Using default X configuration" for every way of not loading anything, so the bug in issue #10874 - a store handed in that the type assertion rejects, leaving a task running on compiled-in defaults - looked exactly like the normal "no data directory configured" case. The reporter had to read the source to work out why their disabled task kept running, and asked for this specifically. Separate the cases. A non-nil store that does not provide the accessor is always a wiring bug and is now logged at warning level, naming the type and the missing method. A read error or a policy that will not apply is also a warning. No persistence configured, and a store with nothing saved yet, stay at V(1): those are normal. Refs #10874 * admin: stop GetTaskPolicy panicking on a maintenance policy that is nil GetTaskPolicy dereferenced its MaintenancePolicy argument to look at TaskPolicies, so IsTaskEnabled, GetMaxConcurrent and GetRepeatInterval all took the admin process down when handed a nil policy. A nil policy is not a programming error here: MaintenanceConfig.Policy is unset until something builds one, DefaultMaintenanceConfig returns a config with no policy at all, and UpdateConfig installs whatever config it is given. Found by calling IsTaskEnabled with the policy from a freshly defaulted MaintenanceConfig. Treat a nil policy as "no entry": no task enabled, the safe concurrency default of 1, and a repeat interval of 0 so callers fall back to their own default instead of reading DefaultRepeatIntervalSeconds off nil. Also add the startup test this was found with. It walks the admin server's startup sequence over a data directory that has balance saved as disabled and checks the state that decides whether issue #10874 happens: the balance detector reports disabled, vacuum stays enabled, and tasks whose config was never saved keep their compiled-in default. Refs #10874 * admin: document the synchronisation SetPolicy would need beyond startup ConfigureTasksFromPolicy now really writes TaskDefinition.Config and TaskDefinition.MaxConcurrent, which the scan loop reads through detector.IsEnabled() with nothing synchronising the two. Every caller runs during admin server startup today, before the scan loop exists, so there is no live race - but the next caller has to add the locking, and the same already applies to UpdateAllConfigs replacing the whole config object. Write it down at the seam instead of leaving it to be rediscovered. Refs #10874
2026-08-28 11:56:07 +00:00 · 2026-08-22 23:41:45 -07:00
parent f710b6003a
commit 8d2c0273bd
19 changed files with 1320 additions and 246 deletions
@@ -278,12 +278,17 @@ func NewAdminServer(masters string, filerGroup string, templateFS http.FileSyste
 		glog.V(1).Infof("No data directory configured, maintenance system will run in memory-only mode (enabled: %v)", maintenanceConfig.Enabled)
 	}

+	// Load saved task configurations from persistence. This has to run before the maintenance
+	// manager is created: creating it applies the maintenance policy to the registered
+	// detectors and schedulers, while this call replaces each task's whole config object, so
+	// running it afterwards would discard what the policy just applied. Both read the same
+	// persisted task config files, so the policy ends up as the last writer and stays
+	// authoritative for the task types it covers.
+	server.loadTaskConfigurationsFromPersistence()
+
 	// Always initialize maintenance manager
 	server.InitMaintenanceManager(maintenanceConfig)

-	// Load saved task configurations from persistence
-	server.loadTaskConfigurationsFromPersistence()
-
 	// Start maintenance manager if enabled
 	if maintenanceConfig.Enabled {
 		go func() {
@@ -1839,7 +1844,16 @@ func (s *AdminServer) ListPluginSchedulerStates() ([]adminplugin.SchedulerJobTyp

 // InitMaintenanceManager initializes the maintenance manager
 func (s *AdminServer) InitMaintenanceManager(config *maintenance.MaintenanceConfig) {
-	s.maintenanceManager = maintenance.NewMaintenanceManager(s, config)
+	// Hand the real config store to the manager so that, if it has to build the maintenance policy
+	// itself, it reads the persisted task configs instead of compiled-in defaults. Only pass it when
+	// a data directory is actually configured: an unconfigured store has nothing to read, and a typed
+	// nil pointer would satisfy the loaders' type assertion and then panic on use.
+	var configPersistence interface{}
+	if s.configPersistence != nil && s.configPersistence.IsConfigured() {
+		configPersistence = s.configPersistence
+	}
+
+	s.maintenanceManager = maintenance.NewMaintenanceManager(s, config, configPersistence)

 	// Set up task persistence if config persistence is available
 	if s.configPersistence != nil {
@@ -14,6 +14,7 @@ import (
 	"github.com/seaweedfs/seaweedfs/weed/glog"
 	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/ec_balance"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/erasure_coding"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/vacuum"
 	"google.golang.org/protobuf/encoding/protojson"
@@ -29,6 +30,7 @@ const (
 	VacuumTaskConfigFile      = "task_vacuum.pb"
 	ECTaskConfigFile          = "task_erasure_coding.pb"
 	BalanceTaskConfigFile     = "task_balance.pb"
+	EcBalanceTaskConfigFile   = "task_ec_balance.pb"
 	ReplicationTaskConfigFile = "task_replication.pb"

 	// JSON reference files
@@ -36,6 +38,7 @@ const (
 	VacuumTaskConfigJSONFile      = "task_vacuum.json"
 	ECTaskConfigJSONFile          = "task_erasure_coding.json"
 	BalanceTaskConfigJSONFile     = "task_balance.json"
+	EcBalanceTaskConfigJSONFile   = "task_ec_balance.json"
 	ReplicationTaskConfigJSONFile = "task_replication.json"

 	// Task persistence subdirectories and settings
@@ -53,6 +56,7 @@ type (
 	VacuumTaskConfig        = worker_pb.VacuumTaskConfig
 	ErasureCodingTaskConfig = worker_pb.ErasureCodingTaskConfig
 	BalanceTaskConfig       = worker_pb.BalanceTaskConfig
+	EcBalanceTaskConfig     = worker_pb.EcBalanceTaskConfig
 	ReplicationTaskConfig   = worker_pb.ReplicationTaskConfig
 )

@@ -156,7 +160,7 @@ func (cp *ConfigPersistence) LoadMaintenanceConfig() (*MaintenanceConfig, error)
 		var config MaintenanceConfig
 		if err := proto.Unmarshal(configData, &config); err == nil {
 			// Always populate policy from separate task configuration files
-			config.Policy = buildPolicyFromTaskConfigs()
+			config.Policy = cp.buildPolicyFromTaskConfigs()
 			return &config, nil
 		}
 	}
@@ -268,6 +272,28 @@ func (cp *ConfigPersistence) RestoreConfig(filename, backupName string) error {
 	return nil
 }

+// Default task policies. These derive from each task's own NewDefaultConfig() so that a
+// task type has exactly one definition of its defaults. They used to be hand-written copies
+// here, and had drifted from the values the tasks themselves and the admin UI schema use:
+// vacuum scanned every 24h instead of 2h, balance every 6h instead of 30m with a 0.1 instead
+// of 0.2 imbalance threshold, and erasure coding every 168h instead of 1h with a 0.90 instead
+// of 0.95 fullness ratio and a 1024MB instead of 30MB minimum volume size.
+func defaultVacuumTaskPolicy() *worker_pb.TaskPolicy {
+	return vacuum.NewDefaultConfig().ToTaskPolicy()
+}
+
+func defaultErasureCodingTaskPolicy() *worker_pb.TaskPolicy {
+	return erasure_coding.NewDefaultConfig().ToTaskPolicy()
+}
+
+func defaultBalanceTaskPolicy() *worker_pb.TaskPolicy {
+	return balance.NewDefaultConfig().ToTaskPolicy()
+}
+
+func defaultEcBalanceTaskPolicy() *worker_pb.TaskPolicy {
+	return ec_balance.NewDefaultConfig().ToTaskPolicy()
+}
+
 // SaveVacuumTaskConfig saves vacuum task configuration to protobuf file
 func (cp *ConfigPersistence) SaveVacuumTaskConfig(config *VacuumTaskConfig) error {
 	return cp.saveTaskConfig(VacuumTaskConfigFile, config)
@@ -288,28 +314,14 @@ func (cp *ConfigPersistence) LoadVacuumTaskConfig() (*VacuumTaskConfig, error) {
 	}

 	// Return default config if no valid config found
-	return &VacuumTaskConfig{
-		GarbageThreshold:  0.3,
-		MinVolumeAgeHours: 24,
-	}, nil
+	return defaultVacuumTaskPolicy().GetVacuumConfig(), nil
 }

 // LoadVacuumTaskPolicy loads complete vacuum task policy from protobuf file
 func (cp *ConfigPersistence) LoadVacuumTaskPolicy() (*worker_pb.TaskPolicy, error) {
 	if cp.dataDir == "" {
 		// Return default policy if no data directory
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         2,
-			RepeatIntervalSeconds: 24 * 3600, // 24 hours in seconds
-			CheckIntervalSeconds:  6 * 3600,  // 6 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_VacuumConfig{
-				VacuumConfig: &worker_pb.VacuumTaskConfig{
-					GarbageThreshold:  0.3,
-					MinVolumeAgeHours: 24,
-				},
-			},
-		}, nil
+		return defaultVacuumTaskPolicy(), nil
 	}

 	confDir := filepath.Join(cp.dataDir, ConfigSubdir)
@@ -318,18 +330,7 @@ func (cp *ConfigPersistence) LoadVacuumTaskPolicy() (*worker_pb.TaskPolicy, erro
 	// Check if file exists
 	if _, err := os.Stat(configPath); os.IsNotExist(err) {
 		// Return default policy if file doesn't exist
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         2,
-			RepeatIntervalSeconds: 24 * 3600, // 24 hours in seconds
-			CheckIntervalSeconds:  6 * 3600,  // 6 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_VacuumConfig{
-				VacuumConfig: &worker_pb.VacuumTaskConfig{
-					GarbageThreshold:  0.3,
-					MinVolumeAgeHours: 24,
-				},
-			},
-		}, nil
+		return defaultVacuumTaskPolicy(), nil
 	}

 	// Read file
@@ -371,32 +372,14 @@ func (cp *ConfigPersistence) LoadErasureCodingTaskConfig() (*ErasureCodingTaskCo
 	}

 	// Return default config if no valid config found
-	return &ErasureCodingTaskConfig{
-		FullnessRatio:    0.9,
-		QuietForSeconds:  3600,
-		MinVolumeSizeMb:  1024,
-		CollectionFilter: "",
-	}, nil
+	return defaultErasureCodingTaskPolicy().GetErasureCodingConfig(), nil
 }

 // LoadErasureCodingTaskPolicy loads complete EC task policy from protobuf file
 func (cp *ConfigPersistence) LoadErasureCodingTaskPolicy() (*worker_pb.TaskPolicy, error) {
 	if cp.dataDir == "" {
 		// Return default policy if no data directory
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         1,
-			RepeatIntervalSeconds: 168 * 3600, // 1 week in seconds
-			CheckIntervalSeconds:  24 * 3600,  // 24 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_ErasureCodingConfig{
-				ErasureCodingConfig: &worker_pb.ErasureCodingTaskConfig{
-					FullnessRatio:    0.9,
-					QuietForSeconds:  3600,
-					MinVolumeSizeMb:  1024,
-					CollectionFilter: "",
-				},
-			},
-		}, nil
+		return defaultErasureCodingTaskPolicy(), nil
 	}

 	confDir := filepath.Join(cp.dataDir, ConfigSubdir)
@@ -405,20 +388,7 @@ func (cp *ConfigPersistence) LoadErasureCodingTaskPolicy() (*worker_pb.TaskPolic
 	// Check if file exists
 	if _, err := os.Stat(configPath); os.IsNotExist(err) {
 		// Return default policy if file doesn't exist
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         1,
-			RepeatIntervalSeconds: 168 * 3600, // 1 week in seconds
-			CheckIntervalSeconds:  24 * 3600,  // 24 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_ErasureCodingConfig{
-				ErasureCodingConfig: &worker_pb.ErasureCodingTaskConfig{
-					FullnessRatio:    0.9,
-					QuietForSeconds:  3600,
-					MinVolumeSizeMb:  1024,
-					CollectionFilter: "",
-				},
-			},
-		}, nil
+		return defaultErasureCodingTaskPolicy(), nil
 	}

 	// Read file
@@ -460,28 +430,14 @@ func (cp *ConfigPersistence) LoadBalanceTaskConfig() (*BalanceTaskConfig, error)
 	}

 	// Return default config if no valid config found
-	return &BalanceTaskConfig{
-		ImbalanceThreshold: 0.1,
-		MinServerCount:     2,
-	}, nil
+	return defaultBalanceTaskPolicy().GetBalanceConfig(), nil
 }

 // LoadBalanceTaskPolicy loads complete balance task policy from protobuf file
 func (cp *ConfigPersistence) LoadBalanceTaskPolicy() (*worker_pb.TaskPolicy, error) {
 	if cp.dataDir == "" {
 		// Return default policy if no data directory
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         1,
-			RepeatIntervalSeconds: 6 * 3600,  // 6 hours in seconds
-			CheckIntervalSeconds:  12 * 3600, // 12 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_BalanceConfig{
-				BalanceConfig: &worker_pb.BalanceTaskConfig{
-					ImbalanceThreshold: 0.1,
-					MinServerCount:     2,
-				},
-			},
-		}, nil
+		return defaultBalanceTaskPolicy(), nil
 	}

 	confDir := filepath.Join(cp.dataDir, ConfigSubdir)
@@ -490,18 +446,7 @@ func (cp *ConfigPersistence) LoadBalanceTaskPolicy() (*worker_pb.TaskPolicy, err
 	// Check if file exists
 	if _, err := os.Stat(configPath); os.IsNotExist(err) {
 		// Return default policy if file doesn't exist
-		return &worker_pb.TaskPolicy{
-			Enabled:               true,
-			MaxConcurrent:         1,
-			RepeatIntervalSeconds: 6 * 3600,  // 6 hours in seconds
-			CheckIntervalSeconds:  12 * 3600, // 12 hours in seconds
-			TaskConfig: &worker_pb.TaskPolicy_BalanceConfig{
-				BalanceConfig: &worker_pb.BalanceTaskConfig{
-					ImbalanceThreshold: 0.1,
-					MinServerCount:     2,
-				},
-			},
-		}, nil
+		return defaultBalanceTaskPolicy(), nil
 	}

 	// Read file
@@ -523,6 +468,60 @@ func (cp *ConfigPersistence) LoadBalanceTaskPolicy() (*worker_pb.TaskPolicy, err
 	return nil, fmt.Errorf("failed to unmarshal balance task configuration")
 }

+// SaveEcBalanceTaskPolicy saves complete EC balance task policy to protobuf file
+func (cp *ConfigPersistence) SaveEcBalanceTaskPolicy(policy *worker_pb.TaskPolicy) error {
+	return cp.saveTaskConfig(EcBalanceTaskConfigFile, policy)
+}
+
+// LoadEcBalanceTaskConfig loads EC balance task configuration from protobuf file
+func (cp *ConfigPersistence) LoadEcBalanceTaskConfig() (*EcBalanceTaskConfig, error) {
+	if taskPolicy, err := cp.LoadEcBalanceTaskPolicy(); err == nil && taskPolicy != nil {
+		if ecBalanceConfig := taskPolicy.GetEcBalanceConfig(); ecBalanceConfig != nil {
+			return ecBalanceConfig, nil
+		}
+	}
+
+	// Return default config if no valid config found
+	return defaultEcBalanceTaskPolicy().GetEcBalanceConfig(), nil
+}
+
+// LoadEcBalanceTaskPolicy loads complete EC balance task policy from protobuf file.
+// ec_balance is registered like the other maintenance tasks and ec_balance.LoadConfigFromPersistence
+// asserts on this accessor, so without it the task could never be configured at all.
+func (cp *ConfigPersistence) LoadEcBalanceTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	if cp.dataDir == "" {
+		// Return default policy if no data directory
+		return defaultEcBalanceTaskPolicy(), nil
+	}
+
+	confDir := filepath.Join(cp.dataDir, ConfigSubdir)
+	configPath := filepath.Join(confDir, EcBalanceTaskConfigFile)
+
+	// Check if file exists
+	if _, err := os.Stat(configPath); os.IsNotExist(err) {
+		// Return default policy if file doesn't exist
+		return defaultEcBalanceTaskPolicy(), nil
+	}
+
+	// Read file
+	configData, err := os.ReadFile(configPath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read EC balance task config file: %w", err)
+	}
+
+	// Try to unmarshal as TaskPolicy
+	var policy worker_pb.TaskPolicy
+	if err := proto.Unmarshal(configData, &policy); err == nil {
+		// Validate that it's actually a TaskPolicy with EC balance config
+		if policy.GetEcBalanceConfig() != nil {
+			glog.V(1).Infof("Loaded EC balance task policy from %s", configPath)
+			return &policy, nil
+		}
+	}
+
+	return nil, fmt.Errorf("failed to unmarshal EC balance task configuration")
+}
+
 // SaveReplicationTaskConfig saves replication task configuration to protobuf file
 func (cp *ConfigPersistence) SaveReplicationTaskConfig(config *ReplicationTaskConfig) error {
 	return cp.saveTaskConfig(ReplicationTaskConfigFile, config)
@@ -632,6 +631,8 @@ func (cp *ConfigPersistence) SaveTaskPolicy(taskType string, policy *worker_pb.T
 		return cp.SaveErasureCodingTaskPolicy(policy)
 	case "balance":
 		return cp.SaveBalanceTaskPolicy(policy)
+	case "ec_balance":
+		return cp.SaveEcBalanceTaskPolicy(policy)
 	case "replication":
 		return cp.SaveReplicationTaskPolicy(policy)
 	}
@@ -687,67 +688,13 @@ func (cp *ConfigPersistence) GetConfigInfo() map[string]interface{} {
 	return info
 }

-// buildPolicyFromTaskConfigs loads task configurations from separate files and builds a MaintenancePolicy
-func buildPolicyFromTaskConfigs() *worker_pb.MaintenancePolicy {
-	policy := &worker_pb.MaintenancePolicy{
-		GlobalMaxConcurrent:          4,
-		DefaultRepeatIntervalSeconds: 6 * 3600,  // 6 hours in seconds
-		DefaultCheckIntervalSeconds:  12 * 3600, // 12 hours in seconds
-		TaskPolicies:                 make(map[string]*worker_pb.TaskPolicy),
-	}
-
-	// Load vacuum task configuration
-	if vacuumConfig := vacuum.LoadConfigFromPersistence(nil); vacuumConfig != nil {
-		policy.TaskPolicies["vacuum"] = &worker_pb.TaskPolicy{
-			Enabled:               vacuumConfig.Enabled,
-			MaxConcurrent:         int32(vacuumConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(vacuumConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(vacuumConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_VacuumConfig{
-				VacuumConfig: &worker_pb.VacuumTaskConfig{
-					GarbageThreshold:  float64(vacuumConfig.GarbageThreshold),
-					MinVolumeAgeHours: int32((vacuumConfig.MinVolumeAgeSeconds + 3599) / 3600), // round up so sub-hour values don't become 0
-				},
-			},
-		}
-	}
-
-	// Load erasure coding task configuration
-	if ecConfig := erasure_coding.LoadConfigFromPersistence(nil); ecConfig != nil {
-		policy.TaskPolicies["erasure_coding"] = &worker_pb.TaskPolicy{
-			Enabled:               ecConfig.Enabled,
-			MaxConcurrent:         int32(ecConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(ecConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(ecConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_ErasureCodingConfig{
-				ErasureCodingConfig: &worker_pb.ErasureCodingTaskConfig{
-					FullnessRatio:    float64(ecConfig.FullnessRatio),
-					QuietForSeconds:  int32(ecConfig.QuietForSeconds),
-					MinVolumeSizeMb:  int32(ecConfig.MinSizeMB),
-					CollectionFilter: ecConfig.CollectionFilter,
-				},
-			},
-		}
-	}
-
-	// Load balance task configuration
-	if balanceConfig := balance.LoadConfigFromPersistence(nil); balanceConfig != nil {
-		policy.TaskPolicies["balance"] = &worker_pb.TaskPolicy{
-			Enabled:               balanceConfig.Enabled,
-			MaxConcurrent:         int32(balanceConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(balanceConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(balanceConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_BalanceConfig{
-				BalanceConfig: &worker_pb.BalanceTaskConfig{
-					ImbalanceThreshold: float64(balanceConfig.ImbalanceThreshold),
-					MinServerCount:     int32(balanceConfig.MinServerCount),
-				},
-			},
-		}
-	}
-
-	glog.V(1).Infof("Built maintenance policy from separate task configs - %d task policies loaded", len(policy.TaskPolicies))
-	return policy
+// buildPolicyFromTaskConfigs builds the maintenance policy from the persisted task configs.
+//
+// The body lives in weed/admin/maintenance because the maintenance manager needs the same
+// policy when it has to build one itself, and this package already imports that one. Keeping
+// a second copy here is what let the two drift apart in the first place.
+func (cp *ConfigPersistence) buildPolicyFromTaskConfigs() *worker_pb.MaintenancePolicy {
+	return maintenance.BuildPolicyFromTaskConfigs(cp)
 }

 // SaveTaskDetail saves detailed task information to disk
@@ -0,0 +1,74 @@
+package dash
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/vacuum"
+)
+
+// TestLoadMaintenanceConfigHonoursPersistedTaskConfigs guards against the regression in
+// https://github.com/seaweedfs/seaweedfs/issues/10874: buildPolicyFromTaskConfigs used to call
+// LoadConfigFromPersistence(nil), which can never satisfy the loaders' type assertion, so every
+// task silently fell back to its compiled-in defaults (Enabled: true) and a task disabled in the
+// admin UI kept being scheduled.
+func TestLoadMaintenanceConfigHonoursPersistedTaskConfigs(t *testing.T) {
+	dir := t.TempDir()
+	cp := NewConfigPersistence(dir)
+
+	// A maintenance.pb must exist, otherwise LoadMaintenanceConfig returns early with defaults.
+	if err := cp.SaveMaintenanceConfig(DefaultMaintenanceConfig()); err != nil {
+		t.Fatalf("save maintenance config: %v", err)
+	}
+
+	// Disable balance and vacuum the way the admin UI does, and change a value that is not a bool
+	// so a fallback to defaults cannot pass by coincidence.
+	disabledBalance := balance.NewDefaultConfig()
+	disabledBalance.Enabled = false
+	disabledBalance.MinServerCount = 7
+	if err := cp.SaveBalanceTaskPolicy(disabledBalance.ToTaskPolicy()); err != nil {
+		t.Fatalf("save balance policy: %v", err)
+	}
+
+	disabledVacuum := vacuum.NewDefaultConfig()
+	disabledVacuum.Enabled = false
+	if err := cp.SaveVacuumTaskPolicy(disabledVacuum.ToTaskPolicy()); err != nil {
+		t.Fatalf("save vacuum policy: %v", err)
+	}
+
+	config, err := cp.LoadMaintenanceConfig()
+	if err != nil {
+		t.Fatalf("load maintenance config: %v", err)
+	}
+	if config.Policy == nil {
+		t.Fatal("policy is nil, want it populated from the persisted task configs")
+	}
+
+	balancePolicy := config.Policy.TaskPolicies["balance"]
+	if balancePolicy == nil {
+		t.Fatal("no balance task policy in the built maintenance policy")
+	}
+	if balancePolicy.Enabled {
+		t.Error("balance enabled = true, want false from the persisted config")
+	}
+	if got := balancePolicy.GetBalanceConfig().GetMinServerCount(); got != 7 {
+		t.Errorf("balance min server count = %d, want persisted 7", got)
+	}
+
+	vacuumPolicy := config.Policy.TaskPolicies["vacuum"]
+	if vacuumPolicy == nil {
+		t.Fatal("no vacuum task policy in the built maintenance policy")
+	}
+	if vacuumPolicy.Enabled {
+		t.Error("vacuum enabled = true, want false from the persisted config")
+	}
+
+	// erasure_coding was never saved, so it keeps the loader's default of enabled.
+	ecPolicy := config.Policy.TaskPolicies["erasure_coding"]
+	if ecPolicy == nil {
+		t.Fatal("no erasure_coding task policy in the built maintenance policy")
+	}
+	if !ecPolicy.Enabled {
+		t.Error("erasure_coding enabled = false, want the default true for a config never saved")
+	}
+}
@@ -0,0 +1,123 @@
+package dash
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/admin/maintenance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/vacuum"
+	"github.com/seaweedfs/seaweedfs/weed/worker/types"
+)
+
+// The task definitions these tests configure are process-global, so put them back the way a
+// fresh process would have them. Passing no config store makes every task fall back to its
+// own NewDefaultConfig, which is exactly the state package init left them in.
+func restoreGlobalTaskState(t *testing.T) {
+	t.Helper()
+
+	t.Cleanup(func() {
+		tasks.GetGlobalConfigUpdateRegistry().UpdateAllConfigs(nil)
+	})
+}
+
+// TestDisabledTaskIsNotScannedAfterStartup walks the admin server's startup sequence over a
+// data directory that has a disabled balance task saved in it, and checks the end state that
+// actually matters: the balance detector reports disabled, so ScanWithTaskDetectors skips it.
+//
+// This is the whole of issue #10874 in one test. The reporter disabled balance, and the
+// scanner kept detecting balance tasks, cancelling them and re-detecting them. Two separate
+// defects had to line up for the disabled flag to survive to here: the policy had to be built
+// from the persisted configs rather than from a nil store, and the policy had to reach
+// detector.IsEnabled() rather than dying in a failed type assertion.
+func TestDisabledTaskIsNotScannedAfterStartup(t *testing.T) {
+	restoreGlobalTaskState(t)
+
+	dir := t.TempDir()
+	cp := NewConfigPersistence(dir)
+
+	// What the admin writes when a user turns balance off, and leaves vacuum on.
+	disabledBalance := balance.NewDefaultConfig()
+	disabledBalance.Enabled = false
+	if err := cp.SaveBalanceTaskPolicy(disabledBalance.ToTaskPolicy()); err != nil {
+		t.Fatalf("save balance policy: %v", err)
+	}
+
+	enabledVacuum := vacuum.NewDefaultConfig()
+	enabledVacuum.Enabled = true
+	if err := cp.SaveVacuumTaskPolicy(enabledVacuum.ToTaskPolicy()); err != nil {
+		t.Fatalf("save vacuum policy: %v", err)
+	}
+
+	// The admin server's startup sequence, in order:
+	// loadTaskConfigurationsFromPersistence, then InitMaintenanceManager.
+	tasks.GetGlobalConfigUpdateRegistry().UpdateAllConfigs(cp)
+
+	maintenanceConfig, err := cp.LoadMaintenanceConfig()
+	if err != nil {
+		t.Fatalf("load maintenance config: %v", err)
+	}
+	manager := maintenance.NewMaintenanceManager(nil, maintenanceConfig, cp)
+	if manager == nil {
+		t.Fatal("NewMaintenanceManager returned nil")
+	}
+
+	registry := tasks.GetGlobalTypesRegistry()
+
+	balanceDetector := registry.GetDetector(types.TaskTypeBalance)
+	if balanceDetector == nil {
+		t.Fatal("no balance detector registered")
+	}
+	if balanceDetector.IsEnabled() {
+		t.Error("balance detector reports enabled after startup over a data directory where " +
+			"balance is saved as disabled; the scanner will keep detecting and cancelling balance tasks")
+	}
+
+	vacuumDetector := registry.GetDetector(types.TaskTypeVacuum)
+	if vacuumDetector == nil {
+		t.Fatal("no vacuum detector registered")
+	}
+	if !vacuumDetector.IsEnabled() {
+		t.Error("vacuum detector reports disabled although vacuum is saved as enabled; " +
+			"the fix must not switch off tasks the user left on")
+	}
+
+	// Tasks the user never touched keep their compiled-in default of enabled rather than
+	// being switched off by a policy entry built from a config that was never saved.
+	for _, taskType := range []types.TaskType{types.TaskTypeErasureCoding, types.TaskTypeECBalance} {
+		detector := registry.GetDetector(taskType)
+		if detector == nil {
+			t.Fatalf("no %s detector registered", taskType)
+		}
+		if !detector.IsEnabled() {
+			t.Errorf("%s detector reports disabled although its config was never saved", taskType)
+		}
+	}
+}
+
+// TestPolicyMirrorsWhatTheDetectorsReport checks that the maintenance policy the queue and
+// the scanner run on agrees with the detectors. A disagreement means one of the two paths
+// into the task configs has gone stale again.
+func TestPolicyMirrorsWhatTheDetectorsReport(t *testing.T) {
+	restoreGlobalTaskState(t)
+
+	dir := t.TempDir()
+	cp := NewConfigPersistence(dir)
+
+	disabledBalance := balance.NewDefaultConfig()
+	disabledBalance.Enabled = false
+	if err := cp.SaveBalanceTaskPolicy(disabledBalance.ToTaskPolicy()); err != nil {
+		t.Fatalf("save balance policy: %v", err)
+	}
+
+	tasks.GetGlobalConfigUpdateRegistry().UpdateAllConfigs(cp)
+	policy := cp.buildPolicyFromTaskConfigs()
+
+	for taskType, detector := range tasks.GetGlobalTypesRegistry().GetAllDetectors() {
+		policyEnabled := maintenance.IsTaskEnabled(policy, maintenance.MaintenanceTaskType(taskType))
+		if policyEnabled != detector.IsEnabled() {
+			t.Errorf("%s: policy says enabled=%v but the detector says enabled=%v",
+				taskType, policyEnabled, detector.IsEnabled())
+		}
+	}
+}
@@ -0,0 +1,178 @@
+package dash
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/ec_balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/erasure_coding"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/vacuum"
+	"google.golang.org/protobuf/proto"
+)
+
+// TestLoadTaskPolicyDefaultsMatchTaskDefaults pins the persistence layer's "nothing saved
+// yet" defaults to each task's own NewDefaultConfig(). They used to be a second, hand-written
+// copy and had drifted: with a data directory but no config file on disk, vacuum ran on a 24h
+// scan interval instead of 2h, balance on 6h with a 0.1 imbalance threshold instead of 30m
+// with 0.2, and erasure coding on 168h with a 0.90 fullness ratio and a 1024MB minimum volume
+// size instead of 1h with 0.95 and 30MB - none of which is what the admin UI shows as the
+// default for those fields.
+func TestLoadTaskPolicyDefaultsMatchTaskDefaults(t *testing.T) {
+	cases := []struct {
+		name string
+		want *worker_pb.TaskPolicy
+		load func(cp *ConfigPersistence) (*worker_pb.TaskPolicy, error)
+	}{
+		{
+			name: "vacuum",
+			want: vacuum.NewDefaultConfig().ToTaskPolicy(),
+			load: func(cp *ConfigPersistence) (*worker_pb.TaskPolicy, error) { return cp.LoadVacuumTaskPolicy() },
+		},
+		{
+			name: "erasure_coding",
+			want: erasure_coding.NewDefaultConfig().ToTaskPolicy(),
+			load: func(cp *ConfigPersistence) (*worker_pb.TaskPolicy, error) {
+				return cp.LoadErasureCodingTaskPolicy()
+			},
+		},
+		{
+			name: "balance",
+			want: balance.NewDefaultConfig().ToTaskPolicy(),
+			load: func(cp *ConfigPersistence) (*worker_pb.TaskPolicy, error) { return cp.LoadBalanceTaskPolicy() },
+		},
+		{
+			name: "ec_balance",
+			want: ec_balance.NewDefaultConfig().ToTaskPolicy(),
+			load: func(cp *ConfigPersistence) (*worker_pb.TaskPolicy, error) { return cp.LoadEcBalanceTaskPolicy() },
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			// Both no-file branches have to agree with the task's own defaults: no data
+			// directory at all, and a data directory that has never been written to.
+			for _, cp := range []*ConfigPersistence{NewConfigPersistence(""), NewConfigPersistence(t.TempDir())} {
+				got, err := tc.load(cp)
+				if err != nil {
+					t.Fatalf("load %s policy: %v", tc.name, err)
+				}
+				if !proto.Equal(got, tc.want) {
+					t.Errorf("%s default policy (dataDir=%q) =\n  %v\nwant NewDefaultConfig().ToTaskPolicy() =\n  %v",
+						tc.name, cp.GetDataDir(), got, tc.want)
+				}
+			}
+		})
+	}
+}
+
+// TestLoadTaskConfigDefaultsMatchTaskDefaults covers the narrower Load*TaskConfig accessors,
+// which carried a third copy of the same defaults.
+func TestLoadTaskConfigDefaultsMatchTaskDefaults(t *testing.T) {
+	cp := NewConfigPersistence(t.TempDir())
+
+	vacuumConfig, err := cp.LoadVacuumTaskConfig()
+	if err != nil {
+		t.Fatalf("load vacuum config: %v", err)
+	}
+	if want := vacuum.NewDefaultConfig().ToTaskPolicy().GetVacuumConfig(); !proto.Equal(vacuumConfig, want) {
+		t.Errorf("vacuum default config = %v, want %v", vacuumConfig, want)
+	}
+
+	ecConfig, err := cp.LoadErasureCodingTaskConfig()
+	if err != nil {
+		t.Fatalf("load erasure coding config: %v", err)
+	}
+	if want := erasure_coding.NewDefaultConfig().ToTaskPolicy().GetErasureCodingConfig(); !proto.Equal(ecConfig, want) {
+		t.Errorf("erasure coding default config = %v, want %v", ecConfig, want)
+	}
+
+	balanceConfig, err := cp.LoadBalanceTaskConfig()
+	if err != nil {
+		t.Fatalf("load balance config: %v", err)
+	}
+	if want := balance.NewDefaultConfig().ToTaskPolicy().GetBalanceConfig(); !proto.Equal(balanceConfig, want) {
+		t.Errorf("balance default config = %v, want %v", balanceConfig, want)
+	}
+}
+
+// TestEcBalanceTaskPolicyRoundTrip checks the accessor ec_balance.LoadConfigFromPersistence
+// asserts on. Before it existed, ec_balance was the one registered maintenance task whose
+// configuration could not be persisted at all.
+func TestEcBalanceTaskPolicyRoundTrip(t *testing.T) {
+	cp := NewConfigPersistence(t.TempDir())
+
+	saved := ec_balance.NewDefaultConfig()
+	saved.Enabled = false
+	saved.MinServerCount = 9
+	saved.ImbalanceThreshold = 0.42
+	saved.CollectionFilter = "pictures"
+
+	if err := cp.SaveEcBalanceTaskPolicy(saved.ToTaskPolicy()); err != nil {
+		t.Fatalf("save ec_balance policy: %v", err)
+	}
+
+	loaded := ec_balance.LoadConfigFromPersistence(cp)
+	if loaded == nil {
+		t.Fatal("ec_balance.LoadConfigFromPersistence returned nil")
+	}
+	if loaded.Enabled {
+		t.Error("ec_balance enabled = true, want the persisted false")
+	}
+	if loaded.MinServerCount != 9 {
+		t.Errorf("ec_balance min server count = %d, want the persisted 9", loaded.MinServerCount)
+	}
+	if loaded.ImbalanceThreshold != 0.42 {
+		t.Errorf("ec_balance imbalance threshold = %v, want the persisted 0.42", loaded.ImbalanceThreshold)
+	}
+	if loaded.CollectionFilter != "pictures" {
+		t.Errorf("ec_balance collection filter = %q, want the persisted %q", loaded.CollectionFilter, "pictures")
+	}
+
+	// The generic dispatcher the maintenance manager uses has to know the type too.
+	if err := cp.SaveTaskPolicy("ec_balance", saved.ToTaskPolicy()); err != nil {
+		t.Errorf("SaveTaskPolicy(ec_balance): %v", err)
+	}
+}
+
+// TestBuildPolicyKeepsTaskSpecificFields guards the fields the hand-written policy builder
+// used to drop on the floor: the erasure coding preferred tags and replica placement, and
+// the balance IO rate limit. Building each entry from the task's own ToTaskPolicy() keeps
+// them, so a value set in admin.toml survives into the maintenance policy.
+func TestBuildPolicyKeepsTaskSpecificFields(t *testing.T) {
+	cp := NewConfigPersistence(t.TempDir())
+
+	ecConfig := erasure_coding.NewDefaultConfig()
+	ecConfig.PreferredTags = []string{"ssd", "archive"}
+	ecConfig.ReplicaPlacement = "020"
+	if err := cp.SaveErasureCodingTaskPolicy(ecConfig.ToTaskPolicy()); err != nil {
+		t.Fatalf("save erasure coding policy: %v", err)
+	}
+
+	balanceConfig := balance.NewDefaultConfig()
+	balanceConfig.IoBytePerSecond = 5 << 20
+	if err := cp.SaveBalanceTaskPolicy(balanceConfig.ToTaskPolicy()); err != nil {
+		t.Fatalf("save balance policy: %v", err)
+	}
+
+	policy := cp.buildPolicyFromTaskConfigs()
+
+	ecPolicy := policy.TaskPolicies["erasure_coding"].GetErasureCodingConfig()
+	if ecPolicy == nil {
+		t.Fatal("no erasure coding config in the built policy")
+	}
+	if got := ecPolicy.GetReplicaPlacement(); got != "020" {
+		t.Errorf("erasure coding replica placement = %q, want the persisted %q", got, "020")
+	}
+	if got := ecPolicy.GetPreferredTags(); len(got) != 2 {
+		t.Errorf("erasure coding preferred tags = %v, want the persisted 2 entries", got)
+	}
+
+	balancePolicy := policy.TaskPolicies["balance"].GetBalanceConfig()
+	if balancePolicy == nil {
+		t.Fatal("no balance config in the built policy")
+	}
+	if got := balancePolicy.GetIoBytePerSecond(); got != 5<<20 {
+		t.Errorf("balance IO limit = %d, want the persisted %d", got, 5<<20)
+	}
+}
@@ -122,6 +122,22 @@ func (s *MaintenanceIntegration) registerAllTasks() {
 	glog.V(1).Infof("Registered tasks: %v", registeredTaskTypes)
 }

+// SetPolicy replaces the maintenance policy the integration configures tasks from and
+// applies it immediately. Without this the integration kept the policy it was built with,
+// so a policy updated at runtime reached the queue but never the detectors that decide
+// which task types are scanned for.
+//
+// Not safe to call concurrently with a running scan. ConfigureTasksFromPolicy writes
+// TaskDefinition.Config and TaskDefinition.MaxConcurrent, which ScanWithTaskDetectors reads
+// through detector.IsEnabled(); nothing synchronises the two. Today every caller runs during
+// admin server startup, before the scan loop exists. Anything that wires this to an HTTP
+// handler has to add that synchronisation first - the same applies to
+// tasks.ConfigUpdateRegistry.UpdateAllConfigs, which replaces TaskDefinition.Config outright.
+func (s *MaintenanceIntegration) SetPolicy(policy *MaintenancePolicy) {
+	s.maintenancePolicy = policy
+	s.ConfigureTasksFromPolicy()
+}
+
 // ConfigureTasksFromPolicy dynamically configures all registered tasks based on the maintenance policy
 func (s *MaintenanceIntegration) ConfigureTasksFromPolicy() {
 	if s.maintenancePolicy == nil {
@@ -155,20 +171,32 @@ func (s *MaintenanceIntegration) configureDetectorFromPolicy(taskType types.Task
 		return
 	}

-	// Apply basic configuration that all detectors should support
-	if basicDetector, ok := detector.(interface{ SetEnabled(bool) }); ok {
-		// Convert task system type to maintenance task type for policy lookup
-		maintenanceTaskType, exists := s.taskTypeMap[taskType]
-		if exists {
-			enabled := IsTaskEnabled(s.maintenancePolicy, maintenanceTaskType)
-			basicDetector.SetEnabled(enabled)
-			glog.V(3).Infof("Set enabled=%v for detector %s", enabled, taskType)
-		}
+	// Convert task system type to maintenance task type for policy lookup
+	maintenanceTaskType, exists := s.taskTypeMap[taskType]
+	if !exists {
+		glog.V(3).Infof("No maintenance task type mapping for %s, skipping configuration", taskType)
+		return
 	}

-	// For detectors that don't implement PolicyConfigurableDetector interface,
-	// they should be updated to implement it for full policy-based configuration
-	glog.V(2).Infof("Detector %s should implement PolicyConfigurableDetector interface for full policy support", taskType)
+	// A task type the policy says nothing about is left alone. IsTaskEnabled reports
+	// false for a missing entry, so applying it unconditionally would silently disable
+	// every task the policy does not list - which is how ec_balance would have been
+	// switched off the moment SetEnabled started working.
+	if GetTaskPolicy(s.maintenancePolicy, maintenanceTaskType) == nil {
+		glog.V(2).Infof("Maintenance policy has no entry for %s, leaving its detector configuration untouched", taskType)
+		return
+	}
+
+	// Apply basic configuration that all detectors should support
+	if basicDetector, ok := detector.(interface{ SetEnabled(bool) }); ok {
+		enabled := IsTaskEnabled(s.maintenancePolicy, maintenanceTaskType)
+		basicDetector.SetEnabled(enabled)
+		glog.V(3).Infof("Set enabled=%v for detector %s", enabled, taskType)
+	} else {
+		// For detectors that don't implement PolicyConfigurableDetector interface,
+		// they should be updated to implement it for full policy-based configuration
+		glog.V(2).Infof("Detector %s supports neither PolicyConfigurableDetector nor SetEnabled, its policy is ignored", taskType)
+	}
 }

 // configureSchedulerFromPolicy configures a scheduler using policy-based configuration
@@ -187,11 +215,21 @@ func (s *MaintenanceIntegration) configureSchedulerFromPolicy(taskType types.Tas
 		return
 	}

+	// Same guard as on the detector side: no policy entry means no opinion, not disabled.
+	if GetTaskPolicy(s.maintenancePolicy, maintenanceTaskType) == nil {
+		glog.V(2).Infof("Maintenance policy has no entry for %s, leaving its scheduler configuration untouched", taskType)
+		return
+	}
+
 	// Set enabled status if scheduler supports it
 	if enableableScheduler, ok := scheduler.(interface{ SetEnabled(bool) }); ok {
 		enabled := IsTaskEnabled(s.maintenancePolicy, maintenanceTaskType)
 		enableableScheduler.SetEnabled(enabled)
 		glog.V(3).Infof("Set enabled=%v for scheduler %s", enabled, taskType)
+	} else {
+		// For schedulers that don't implement PolicyConfigurableScheduler interface,
+		// they should be updated to implement it for full policy-based configuration
+		glog.V(2).Infof("Scheduler %s supports neither PolicyConfigurableScheduler nor SetEnabled, its policy is ignored", taskType)
 	}

 	// Set max concurrent if scheduler supports it
@@ -202,10 +240,6 @@ func (s *MaintenanceIntegration) configureSchedulerFromPolicy(taskType types.Tas
 			glog.V(3).Infof("Set max concurrent=%d for scheduler %s", maxConcurrent, taskType)
 		}
 	}
-
-	// For schedulers that don't implement PolicyConfigurableScheduler interface,
-	// they should be updated to implement it for full policy-based configuration
-	glog.V(2).Infof("Scheduler %s should implement PolicyConfigurableScheduler interface for full policy support", taskType)
 }

 // ScanWithTaskDetectors performs a scan using the task system
@@ -10,12 +10,29 @@ import (
 	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
 	stats_collect "github.com/seaweedfs/seaweedfs/weed/stats"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/balance"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/ec_balance"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/erasure_coding"
 	"github.com/seaweedfs/seaweedfs/weed/worker/tasks/vacuum"
+	"github.com/seaweedfs/seaweedfs/weed/worker/types"
 )

-// buildPolicyFromTaskConfigs loads task configurations from separate files and builds a MaintenancePolicy
-func buildPolicyFromTaskConfigs() *worker_pb.MaintenancePolicy {
+// BuildPolicyFromTaskConfigs loads each registered task's configuration and builds the
+// MaintenancePolicy the maintenance system runs on.
+//
+// Every entry is produced by the task's own ToTaskPolicy(), so a policy entry always carries
+// exactly what that task's config holds. Hand-copying the fields here instead made this a
+// second, silently diverging definition of every task's policy: it dropped the erasure
+// coding preferred tags and replica placement and the balance IO rate limit outright.
+//
+// Every task registered through base.RegisterTask needs an entry, because a task type the
+// policy does not list has no enabled flag and no concurrency limit of its own -
+// IsTaskEnabled reports false for a missing entry.
+//
+// configPersistence is duck-typed as interface{} because weed/admin/dash already imports this
+// package, so importing *dash.ConfigPersistence back here would create an import cycle. It must be
+// a value implementing the LoadXTaskPolicy() accessors the task loaders assert on; passing nil (or
+// anything else) makes every task fall back to its compiled-in defaults.
+func BuildPolicyFromTaskConfigs(configPersistence interface{}) *worker_pb.MaintenancePolicy {
 	policy := &worker_pb.MaintenancePolicy{
 		GlobalMaxConcurrent:          4,
 		DefaultRepeatIntervalSeconds: 6 * 3600,  // 6 hours in seconds
@@ -23,54 +40,20 @@ func buildPolicyFromTaskConfigs() *worker_pb.MaintenancePolicy {
 		TaskPolicies:                 make(map[string]*worker_pb.TaskPolicy),
 	}

-	// Load vacuum task configuration
-	if vacuumConfig := vacuum.LoadConfigFromPersistence(nil); vacuumConfig != nil {
-		policy.TaskPolicies["vacuum"] = &worker_pb.TaskPolicy{
-			Enabled:               vacuumConfig.Enabled,
-			MaxConcurrent:         int32(vacuumConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(vacuumConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(vacuumConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_VacuumConfig{
-				VacuumConfig: &worker_pb.VacuumTaskConfig{
-					GarbageThreshold:  float64(vacuumConfig.GarbageThreshold),
-					MinVolumeAgeHours: int32((vacuumConfig.MinVolumeAgeSeconds + 3599) / 3600), // round up so sub-hour values don't become 0
-				},
-			},
-		}
+	if vacuumConfig := vacuum.LoadConfigFromPersistence(configPersistence); vacuumConfig != nil {
+		policy.TaskPolicies[string(types.TaskTypeVacuum)] = vacuumConfig.ToTaskPolicy()
 	}

-	// Load erasure coding task configuration
-	if ecConfig := erasure_coding.LoadConfigFromPersistence(nil); ecConfig != nil {
-		policy.TaskPolicies["erasure_coding"] = &worker_pb.TaskPolicy{
-			Enabled:               ecConfig.Enabled,
-			MaxConcurrent:         int32(ecConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(ecConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(ecConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_ErasureCodingConfig{
-				ErasureCodingConfig: &worker_pb.ErasureCodingTaskConfig{
-					FullnessRatio:    float64(ecConfig.FullnessRatio),
-					QuietForSeconds:  int32(ecConfig.QuietForSeconds),
-					MinVolumeSizeMb:  int32(ecConfig.MinSizeMB),
-					CollectionFilter: ecConfig.CollectionFilter,
-				},
-			},
-		}
+	if ecConfig := erasure_coding.LoadConfigFromPersistence(configPersistence); ecConfig != nil {
+		policy.TaskPolicies[string(types.TaskTypeErasureCoding)] = ecConfig.ToTaskPolicy()
 	}

-	// Load balance task configuration
-	if balanceConfig := balance.LoadConfigFromPersistence(nil); balanceConfig != nil {
-		policy.TaskPolicies["balance"] = &worker_pb.TaskPolicy{
-			Enabled:               balanceConfig.Enabled,
-			MaxConcurrent:         int32(balanceConfig.MaxConcurrent),
-			RepeatIntervalSeconds: int32(balanceConfig.ScanIntervalSeconds),
-			CheckIntervalSeconds:  int32(balanceConfig.ScanIntervalSeconds),
-			TaskConfig: &worker_pb.TaskPolicy_BalanceConfig{
-				BalanceConfig: &worker_pb.BalanceTaskConfig{
-					ImbalanceThreshold: float64(balanceConfig.ImbalanceThreshold),
-					MinServerCount:     int32(balanceConfig.MinServerCount),
-				},
-			},
-		}
+	if balanceConfig := balance.LoadConfigFromPersistence(configPersistence); balanceConfig != nil {
+		policy.TaskPolicies[string(types.TaskTypeBalance)] = balanceConfig.ToTaskPolicy()
+	}
+
+	if ecBalanceConfig := ec_balance.LoadConfigFromPersistence(configPersistence); ecBalanceConfig != nil {
+		policy.TaskPolicies[string(types.TaskTypeECBalance)] = ecBalanceConfig.ToTaskPolicy()
 	}

 	glog.V(1).Infof("Built maintenance policy from separate task configs - %d task policies loaded", len(policy.TaskPolicies))
@@ -94,8 +77,12 @@ type MaintenanceManager struct {
 	scanInProgress bool
 }

-// NewMaintenanceManager creates a new maintenance manager
-func NewMaintenanceManager(adminClient AdminClient, config *MaintenanceConfig) *MaintenanceManager {
+// NewMaintenanceManager creates a new maintenance manager.
+//
+// configPersistence is the config store to read persisted task configs from when the policy has to
+// be built here. See BuildPolicyFromTaskConfigs for why it is duck-typed; pass nil when no config
+// store is available.
+func NewMaintenanceManager(adminClient AdminClient, config *MaintenanceConfig, configPersistence interface{}) *MaintenanceManager {
 	if config == nil {
 		config = DefaultMaintenanceConfig()
 	}
@@ -104,7 +91,7 @@ func NewMaintenanceManager(adminClient AdminClient, config *MaintenanceConfig) *
 	policy := config.Policy
 	if policy == nil {
 		// Fallback: build policy from separate task configuration files if not already populated
-		policy = buildPolicyFromTaskConfigs()
+		policy = BuildPolicyFromTaskConfigs(configPersistence)
 	}

 	queue := NewMaintenanceQueue(policy)
@@ -132,7 +119,9 @@ func (mm *MaintenanceManager) Start() error {
 		return fmt.Errorf("invalid maintenance configuration: %w", err)
 	}

+	mm.mutex.Lock()
 	mm.running = true
+	mm.mutex.Unlock()

 	// Start background processes
 	go mm.scanLoop()
@@ -178,30 +167,54 @@ func (mm *MaintenanceManager) validateConfig() error {
 	return nil
 }

-// IsRunning returns whether the maintenance manager is currently running
+// IsRunning returns whether the maintenance manager is currently running.
+// running is guarded by mm.mutex because the background loops read it on every
+// iteration while Start and Stop are called from the admin server's goroutines.
 func (mm *MaintenanceManager) IsRunning() bool {
+	mm.mutex.RLock()
+	defer mm.mutex.RUnlock()
 	return mm.running
 }

-// Stop terminates the maintenance manager
+// Stop terminates the maintenance manager. It is a no-op when the manager is not
+// running, so a second call cannot close the already closed stop channel.
 func (mm *MaintenanceManager) Stop() {
+	mm.mutex.Lock()
+	if !mm.running {
+		mm.mutex.Unlock()
+		return
+	}
 	mm.running = false
 	close(mm.stopChan)
+	mm.mutex.Unlock()
+
 	glog.Infof("Maintenance manager stopped")
 }

 // scanLoop periodically scans for maintenance tasks with adaptive timing
 func (mm *MaintenanceManager) scanLoop() {
 	scanInterval := time.Duration(mm.config.ScanIntervalSeconds) * time.Second
-	ticker := time.NewTicker(scanInterval)
-	defer ticker.Stop()

-	for mm.running {
+	// activeInterval is the interval the ticker is actually running at right now. It has
+	// to be tracked separately from the configured scanInterval, because the error backoff
+	// replaces the ticker with a much shorter one. Comparing the target against the
+	// configured interval instead never restores the normal cadence: once the errors stop,
+	// getScanInterval returns scanInterval again, the comparison comes out false, and the
+	// ticker is left at the backoff delay. A single transient scan failure therefore pinned
+	// the scanner to one scan per second forever - see issue #10874, where that produced a
+	// ~658 KB/s log flood and 193k orphaned task files.
+	activeInterval := scanInterval
+	ticker := time.NewTicker(activeInterval)
+	// Wrapped in a closure so the replacement ticker is stopped, not the one that happened
+	// to be current when the defer was registered.
+	defer func() { ticker.Stop() }()
+
+	for mm.IsRunning() {
 		select {
 		case <-mm.stopChan:
 			return
 		case <-ticker.C:
-			glog.V(1).Infof("Performing maintenance scan every %v", scanInterval)
+			glog.V(1).Infof("Performing maintenance scan every %v", activeInterval)

 			// Use the same synchronization as TriggerScan to prevent concurrent scans
 			if err := mm.triggerScanInternal(false); err != nil {
@@ -211,10 +224,13 @@ func (mm *MaintenanceManager) scanLoop() {
 			// Adjust ticker interval based on error state (read error state safely)
 			currentInterval := mm.getScanInterval(scanInterval)

-			// Reset ticker with new interval if needed
-			if currentInterval != scanInterval {
+			// Reset ticker whenever the target differs from what the ticker is running at,
+			// which covers both entering the backoff and returning to the normal cadence.
+			if currentInterval != activeInterval {
 				ticker.Stop()
 				ticker = time.NewTicker(currentInterval)
+				glog.V(1).Infof("Maintenance scan cadence changed from %v to %v", activeInterval, currentInterval)
+				activeInterval = currentInterval
 			}
 		}
 	}
@@ -246,7 +262,7 @@ func (mm *MaintenanceManager) cleanupLoop() {
 	ticker := time.NewTicker(cleanupInterval)
 	defer ticker.Stop()

-	for mm.running {
+	for mm.IsRunning() {
 		select {
 		case <-mm.stopChan:
 			return
@@ -263,7 +279,7 @@ func (mm *MaintenanceManager) topologyStatusLoop() {
 	ticker := time.NewTicker(statusInterval)
 	defer ticker.Stop()

-	for mm.running {
+	for mm.IsRunning() {
 		select {
 		case <-mm.stopChan:
 			return
@@ -532,12 +548,15 @@ func (mm *MaintenanceManager) TriggerScan() error {

 // triggerScanInternal handles both manual and automatic scan triggers
 func (mm *MaintenanceManager) triggerScanInternal(isManual bool) error {
+	// running and scanInProgress are checked under one lock so a Stop that lands
+	// between the two checks cannot leave a scan running after shutdown.
+	mm.mutex.Lock()
 	if !mm.running {
+		mm.mutex.Unlock()
 		return fmt.Errorf("maintenance manager is not running")
 	}

 	// Prevent multiple concurrent scans
-	mm.mutex.Lock()
 	if mm.scanInProgress {
 		mm.mutex.Unlock()
 		if isManual {
@@ -569,6 +588,14 @@ func (mm *MaintenanceManager) UpdateConfig(config *MaintenanceConfig) error {
 		mm.saveTaskConfigsFromPolicy(config.Policy)
 	}

+	// The integration holds its own reference to the policy and is what pushes the
+	// enabled flag and the concurrency limit into the registered detectors and
+	// schedulers. Without this the queue and the scanner saw the new policy while the
+	// detectors kept scanning under the old one until the next restart.
+	if mm.scanner != nil && mm.scanner.integration != nil {
+		mm.scanner.integration.SetPolicy(config.Policy)
+	}
+
 	glog.V(1).Infof("Maintenance configuration updated")
 	return nil
 }
@@ -10,7 +10,7 @@ func TestMaintenanceManager_ErrorHandling(t *testing.T) {
 	config := DefaultMaintenanceConfig()
 	config.ScanIntervalSeconds = 1 // Short interval for testing (1 second)

-	manager := NewMaintenanceManager(nil, config)
+	manager := NewMaintenanceManager(nil, config, nil)

 	// Test initial state
 	if manager.errorCount != 0 {
@@ -96,7 +96,7 @@ func TestIsConnectionError(t *testing.T) {

 func TestMaintenanceManager_GetErrorState(t *testing.T) {
 	config := DefaultMaintenanceConfig()
-	manager := NewMaintenanceManager(nil, config)
+	manager := NewMaintenanceManager(nil, config, nil)

 	// Test initial state
 	errorCount, lastError, backoffDelay := manager.GetErrorState()
@@ -118,7 +118,7 @@ func TestMaintenanceManager_GetErrorState(t *testing.T) {

 func TestMaintenanceManager_LogThrottling(t *testing.T) {
 	config := DefaultMaintenanceConfig()
-	manager := NewMaintenanceManager(nil, config)
+	manager := NewMaintenanceManager(nil, config, nil)

 	// This is a basic test to ensure the error handling doesn't panic
 	// In practice, you'd want to capture log output to verify throttling
@@ -0,0 +1,134 @@
+package maintenance
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
+)
+
+// stubConfigPersistence implements the LoadXTaskPolicy accessors that the task config loaders
+// type-assert on. The real implementation is *dash.ConfigPersistence, which this package cannot
+// import: weed/admin/dash already imports weed/admin/maintenance, so the dependency only runs one
+// way and the persistence argument has to stay duck-typed.
+type stubConfigPersistence struct {
+	vacuum    *worker_pb.TaskPolicy
+	ec        *worker_pb.TaskPolicy
+	balance   *worker_pb.TaskPolicy
+	ecBalance *worker_pb.TaskPolicy
+}
+
+func (s *stubConfigPersistence) LoadVacuumTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	return s.vacuum, nil
+}
+
+func (s *stubConfigPersistence) LoadErasureCodingTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	return s.ec, nil
+}
+
+func (s *stubConfigPersistence) LoadBalanceTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	return s.balance, nil
+}
+
+func (s *stubConfigPersistence) LoadEcBalanceTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	return s.ecBalance, nil
+}
+
+func disabledStub() *stubConfigPersistence {
+	return &stubConfigPersistence{
+		vacuum: &worker_pb.TaskPolicy{
+			Enabled:               false,
+			MaxConcurrent:         2,
+			RepeatIntervalSeconds: 2 * 3600,
+			TaskConfig: &worker_pb.TaskPolicy_VacuumConfig{
+				VacuumConfig: &worker_pb.VacuumTaskConfig{GarbageThreshold: 0.3, MinVolumeAgeHours: 24},
+			},
+		},
+		ec: &worker_pb.TaskPolicy{
+			Enabled:               false,
+			MaxConcurrent:         1,
+			RepeatIntervalSeconds: 3600,
+			TaskConfig: &worker_pb.TaskPolicy_ErasureCodingConfig{
+				ErasureCodingConfig: &worker_pb.ErasureCodingTaskConfig{FullnessRatio: 0.95, QuietForSeconds: 3600, MinVolumeSizeMb: 30},
+			},
+		},
+		balance: &worker_pb.TaskPolicy{
+			Enabled:               false,
+			MaxConcurrent:         1,
+			RepeatIntervalSeconds: 30 * 60,
+			TaskConfig: &worker_pb.TaskPolicy_BalanceConfig{
+				BalanceConfig: &worker_pb.BalanceTaskConfig{ImbalanceThreshold: 0.2, MinServerCount: 7},
+			},
+		},
+		ecBalance: &worker_pb.TaskPolicy{
+			Enabled:               false,
+			MaxConcurrent:         1,
+			RepeatIntervalSeconds: 60 * 60,
+			TaskConfig: &worker_pb.TaskPolicy_EcBalanceConfig{
+				EcBalanceConfig: &worker_pb.EcBalanceTaskConfig{ImbalanceThreshold: 0.2, MinServerCount: 5},
+			},
+		},
+	}
+}
+
+// TestBuildPolicyFromTaskConfigsUsesPersistence covers the bug reported in
+// https://github.com/seaweedfs/seaweedfs/issues/10874: the persistence argument used to be a
+// literal nil, which no type assertion can satisfy, so a task disabled on disk came back enabled.
+func TestBuildPolicyFromTaskConfigsUsesPersistence(t *testing.T) {
+	policy := BuildPolicyFromTaskConfigs(disabledStub())
+
+	for _, taskType := range []string{"vacuum", "erasure_coding", "balance", "ec_balance"} {
+		taskPolicy := policy.TaskPolicies[taskType]
+		if taskPolicy == nil {
+			t.Fatalf("no %s task policy built", taskType)
+		}
+		if taskPolicy.Enabled {
+			t.Errorf("%s enabled = true, want false from the persisted config", taskType)
+		}
+	}
+
+	if got := policy.TaskPolicies["balance"].GetBalanceConfig().GetMinServerCount(); got != 7 {
+		t.Errorf("balance min server count = %d, want persisted 7", got)
+	}
+}
+
+// TestBuildPolicyFromTaskConfigsWithoutPersistence keeps the documented fallback: with no config
+// store there is nothing to read, so the compiled-in defaults apply.
+func TestBuildPolicyFromTaskConfigsWithoutPersistence(t *testing.T) {
+	policy := BuildPolicyFromTaskConfigs(nil)
+
+	for _, taskType := range []string{"vacuum", "erasure_coding", "balance", "ec_balance"} {
+		taskPolicy := policy.TaskPolicies[taskType]
+		if taskPolicy == nil {
+			t.Fatalf("no %s task policy built", taskType)
+		}
+		if !taskPolicy.Enabled {
+			t.Errorf("%s enabled = false, want the compiled-in default true", taskType)
+		}
+	}
+}
+
+// TestNewMaintenanceManagerUsesPersistenceForPolicyFallback covers the path the admin server takes
+// when no maintenance.pb has been written yet: the config carries no policy, so the manager builds
+// one itself and must read the persisted task configs to do it.
+func TestNewMaintenanceManagerUsesPersistenceForPolicyFallback(t *testing.T) {
+	config := DefaultMaintenanceConfig()
+	if config.Policy != nil {
+		t.Fatal("default config unexpectedly carries a policy, test no longer covers the fallback")
+	}
+
+	manager := NewMaintenanceManager(nil, config, disabledStub())
+
+	policy := manager.queue.policy
+	if policy == nil {
+		t.Fatal("queue policy is nil")
+	}
+	if IsTaskEnabled(policy, MaintenanceTaskType("balance")) {
+		t.Error("balance enabled = true, want false from the persisted config")
+	}
+	if IsTaskEnabled(policy, MaintenanceTaskType("vacuum")) {
+		t.Error("vacuum enabled = true, want false from the persisted config")
+	}
+	if manager.scanner.policy != policy {
+		t.Error("scanner and queue disagree on the policy")
+	}
+}
@@ -0,0 +1,209 @@
+package maintenance
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
+	"github.com/seaweedfs/seaweedfs/weed/worker/tasks"
+	"github.com/seaweedfs/seaweedfs/weed/worker/types"
+)
+
+// The detectors and schedulers live in a process-global registry, so these tests restore
+// whatever they change. Otherwise a test that disables a task leaks that state into every
+// later test in the package.
+func snapshotDetectorState(t *testing.T) {
+	t.Helper()
+
+	registry := tasks.GetGlobalTypesRegistry()
+	enabled := make(map[types.TaskType]bool)
+	maxConcurrent := make(map[types.TaskType]int)
+	for taskType, detector := range registry.GetAllDetectors() {
+		enabled[taskType] = detector.IsEnabled()
+	}
+	for taskType, scheduler := range registry.GetAllSchedulers() {
+		maxConcurrent[taskType] = scheduler.GetMaxConcurrent()
+	}
+
+	t.Cleanup(func() {
+		for taskType, detector := range registry.GetAllDetectors() {
+			if setter, ok := detector.(interface{ SetEnabled(bool) }); ok {
+				setter.SetEnabled(enabled[taskType])
+			}
+		}
+		for taskType, scheduler := range registry.GetAllSchedulers() {
+			if setter, ok := scheduler.(interface{ SetMaxConcurrent(int) }); ok {
+				setter.SetMaxConcurrent(maxConcurrent[taskType])
+			}
+		}
+	})
+}
+
+// TestPolicyReachesRegisteredDetectors is the regression test for the half of issue #10874
+// that a corrected policy alone did not fix: MaintenanceIntegration pushes the policy into
+// detectors and schedulers through interface{ SetEnabled(bool) } and
+// interface{ SetMaxConcurrent(int) } type assertions, but every task is backed by
+// base.GenericDetector/base.GenericScheduler, which implemented neither. The assertions
+// failed silently for every task on every startup, so the policy never reached
+// detector.IsEnabled() - which is what ScanWithTaskDetectors gates scanning on.
+func TestPolicyReachesRegisteredDetectors(t *testing.T) {
+	snapshotDetectorState(t)
+
+	registry := tasks.GetGlobalTypesRegistry()
+	if len(registry.GetAllDetectors()) == 0 {
+		t.Fatal("no detectors registered, the test cannot prove anything")
+	}
+
+	// Enable everything first so the disabling below cannot pass by accident.
+	policy := policyWithAllTasks(t, true)
+	NewMaintenanceIntegration(NewMaintenanceQueue(policy), policy)
+
+	for taskType, detector := range registry.GetAllDetectors() {
+		if !detector.IsEnabled() {
+			t.Fatalf("detector %s is disabled after an all-enabled policy was applied", taskType)
+		}
+	}
+
+	// Now disable everything through the policy and check it lands on the detectors.
+	policy = policyWithAllTasks(t, false)
+	NewMaintenanceIntegration(NewMaintenanceQueue(policy), policy)
+
+	for taskType, detector := range registry.GetAllDetectors() {
+		if detector.IsEnabled() {
+			t.Errorf("detector %s still reports enabled after the policy disabled it; "+
+				"the policy is not reaching the flag ScanWithTaskDetectors gates on", taskType)
+		}
+	}
+	for taskType, scheduler := range registry.GetAllSchedulers() {
+		if scheduler.IsEnabled() {
+			t.Errorf("scheduler %s still reports enabled after the policy disabled it", taskType)
+		}
+	}
+}
+
+// TestPolicyMaxConcurrentReachesSchedulers covers the SetMaxConcurrent half of the same
+// wiring. GetMaxConcurrent is what MaintenanceQueue.getMaxConcurrentForTaskType asks before
+// starting another task of a type.
+func TestPolicyMaxConcurrentReachesSchedulers(t *testing.T) {
+	snapshotDetectorState(t)
+
+	const wantMaxConcurrent = 7
+
+	policy := policyWithAllTasks(t, true)
+	for _, taskPolicy := range policy.TaskPolicies {
+		taskPolicy.MaxConcurrent = wantMaxConcurrent
+	}
+	NewMaintenanceIntegration(NewMaintenanceQueue(policy), policy)
+
+	registry := tasks.GetGlobalTypesRegistry()
+	for taskType, scheduler := range registry.GetAllSchedulers() {
+		if _, covered := policy.TaskPolicies[string(taskType)]; !covered {
+			continue
+		}
+		if got := scheduler.GetMaxConcurrent(); got != wantMaxConcurrent {
+			t.Errorf("scheduler %s max concurrent = %d, want %d from the policy", taskType, got, wantMaxConcurrent)
+		}
+	}
+}
+
+// TestPolicyWithoutEntryLeavesTaskAlone guards the direction that would have been a silent
+// outage: IsTaskEnabled reports false for a task type the policy does not list, so applying
+// it unconditionally would disable every task the policy has no entry for.
+func TestPolicyWithoutEntryLeavesTaskAlone(t *testing.T) {
+	snapshotDetectorState(t)
+
+	registry := tasks.GetGlobalTypesRegistry()
+
+	// Start from a policy that enables everything.
+	enabling := policyWithAllTasks(t, true)
+	NewMaintenanceIntegration(NewMaintenanceQueue(enabling), enabling)
+
+	// An empty policy has an entry for nothing at all.
+	empty := &MaintenancePolicy{TaskPolicies: make(map[string]*worker_pb.TaskPolicy)}
+	NewMaintenanceIntegration(NewMaintenanceQueue(empty), empty)
+
+	for taskType, detector := range registry.GetAllDetectors() {
+		if !detector.IsEnabled() {
+			t.Errorf("detector %s was disabled by a policy that has no entry for it; "+
+				"a missing entry means no opinion, not disabled", taskType)
+		}
+	}
+}
+
+// TestBuildPolicyCoversEveryRegisteredTask keeps BuildPolicyFromTaskConfigs and the task
+// registry in step. A registered task with no policy entry has no enabled flag and no
+// concurrency limit of its own, which is the state ec_balance was in.
+func TestBuildPolicyCoversEveryRegisteredTask(t *testing.T) {
+	policy := BuildPolicyFromTaskConfigs(nil)
+
+	for taskType := range tasks.GetGlobalTypesRegistry().GetAllDetectors() {
+		if _, ok := policy.TaskPolicies[string(taskType)]; !ok {
+			t.Errorf("task %s is registered as a detector but BuildPolicyFromTaskConfigs "+
+				"builds no policy entry for it, so IsTaskEnabled reports false for it", taskType)
+		}
+	}
+}
+
+// TestBuildPolicyIncludesEcBalance pins the specific gap above.
+func TestBuildPolicyIncludesEcBalance(t *testing.T) {
+	policy := BuildPolicyFromTaskConfigs(nil)
+
+	ecBalance := policy.TaskPolicies[string(types.TaskTypeECBalance)]
+	if ecBalance == nil {
+		t.Fatal("no ec_balance entry in the built maintenance policy")
+	}
+	if !IsTaskEnabled(policy, MaintenanceTaskType(types.TaskTypeECBalance)) {
+		t.Error("ec_balance reports disabled with no persisted config, want the compiled-in default of enabled")
+	}
+	if ecBalance.GetEcBalanceConfig() == nil {
+		t.Error("ec_balance policy entry carries no EcBalanceConfig")
+	}
+}
+
+// policyWithAllTasks builds a policy that has an entry for every registered task type,
+// all sharing the same enabled flag.
+func policyWithAllTasks(t *testing.T, enabled bool) *MaintenancePolicy {
+	t.Helper()
+
+	policy := &MaintenancePolicy{
+		GlobalMaxConcurrent: 4,
+		TaskPolicies:        make(map[string]*worker_pb.TaskPolicy),
+	}
+	for taskType := range tasks.GetGlobalTypesRegistry().GetAllDetectors() {
+		policy.TaskPolicies[string(taskType)] = &worker_pb.TaskPolicy{
+			Enabled:               enabled,
+			MaxConcurrent:         1,
+			RepeatIntervalSeconds: 3600,
+		}
+	}
+	return policy
+}
+
+// TestPolicyHelpersTolerateNilPolicy pins the nil handling in the exported policy helpers.
+// MaintenanceConfig.Policy is nil until something builds one, and UpdateConfig accepts a
+// config that has none, so these are reachable with a nil policy - GetTaskPolicy used to
+// dereference it and take the admin process down.
+func TestPolicyHelpersTolerateNilPolicy(t *testing.T) {
+	const taskType = MaintenanceTaskType("balance")
+
+	if got := GetTaskPolicy(nil, taskType); got != nil {
+		t.Errorf("GetTaskPolicy(nil) = %v, want nil", got)
+	}
+	if IsTaskEnabled(nil, taskType) {
+		t.Error("IsTaskEnabled(nil) = true, want false")
+	}
+	if got := GetMaxConcurrent(nil, taskType); got != 1 {
+		t.Errorf("GetMaxConcurrent(nil) = %d, want the safe default 1", got)
+	}
+	if got := GetRepeatInterval(nil, taskType); got != 0 {
+		t.Errorf("GetRepeatInterval(nil) = %d, want 0 so callers fall back to their own default", got)
+	}
+
+	// A policy that exists but lists nothing must behave the same way.
+	empty := &MaintenancePolicy{}
+	if got := GetTaskPolicy(empty, taskType); got != nil {
+		t.Errorf("GetTaskPolicy(empty) = %v, want nil", got)
+	}
+	if IsTaskEnabled(empty, taskType) {
+		t.Error("IsTaskEnabled(empty) = true, want false")
+	}
+}
@@ -618,7 +618,7 @@ func TestMaintenanceQueue_StaleWorkerCapacityRelease(t *testing.T) {
 func TestMaintenanceManager_CancelTaskCapacityRelease(t *testing.T) {
 	// Setup Manager
 	config := DefaultMaintenanceConfig()
-	mm := NewMaintenanceManager(nil, config)
+	mm := NewMaintenanceManager(nil, config, nil)
 	integration := mm.scanner.integration
 	mq := mm.queue
 	at := integration.GetActiveTopology()
@@ -0,0 +1,168 @@
+package maintenance
+
+import (
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/master_pb"
+)
+
+// scanCadenceClient is a minimal AdminClient whose first call blocks until the test
+// releases it. Blocking the first scan is what makes the cadence test deterministic:
+// the scan loop evaluates the error state right after triggering a scan, and that scan
+// runs in its own goroutine, so without the block the loop could observe the error
+// counter either before or after the scan finished.
+type scanCadenceClient struct {
+	mu      sync.Mutex
+	calls   int
+	release chan struct{}
+}
+
+func (c *scanCadenceClient) WithMasterClient(fn func(client master_pb.SeaweedClient) error) error {
+	c.mu.Lock()
+	c.calls++
+	first := c.calls == 1
+	c.mu.Unlock()
+
+	if first {
+		<-c.release
+	}
+
+	// Returning nil without invoking fn yields an empty, successful scan.
+	return nil
+}
+
+func (c *scanCadenceClient) callCount() int {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.calls
+}
+
+// TestScanLoopRestoresIntervalAfterBackoff is the regression test for the scan flood in
+// https://github.com/seaweedfs/seaweedfs/issues/10874. The loop shortens its ticker to the
+// error backoff delay after a failed scan. It used to compare the target interval against
+// the *configured* scan interval rather than against the interval the ticker was actually
+// running at, so once the errors stopped the comparison came out false and the ticker was
+// never restored: one transient failure pinned the scanner to one scan per second for as
+// long as the process lived.
+//
+// The test seeds the error state, lets the loop drop into the 1s backoff, then lets a scan
+// succeed and asserts the loop goes back to the configured 3s cadence instead of keeping
+// the 1s one.
+func TestScanLoopRestoresIntervalAfterBackoff(t *testing.T) {
+	const baseInterval = 3 * time.Second
+
+	client := &scanCadenceClient{release: make(chan struct{})}
+
+	config := DefaultMaintenanceConfig()
+	config.ScanIntervalSeconds = int32(baseInterval / time.Second)
+	manager := NewMaintenanceManager(client, config, nil)
+
+	// Seed a failed scan so the very first cadence decision drops to the backoff delay.
+	// backoffDelay is what getScanInterval returns while errorCount > 0.
+	manager.mutex.Lock()
+	manager.errorCount = 1
+	manager.backoffDelay = time.Second
+	manager.running = true
+	manager.mutex.Unlock()
+
+	go manager.scanLoop()
+	defer manager.Stop()
+
+	// First tick at ~3s: the scan blocks in the client, so the loop still sees errorCount == 1
+	// and switches the ticker to the 1s backoff.
+	deadline := time.Now().Add(baseInterval + 2*time.Second)
+	for client.callCount() == 0 {
+		if time.Now().After(deadline) {
+			t.Fatal("scan loop never triggered its first scan")
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+
+	// Let the blocked scan complete successfully, which clears the error state.
+	close(client.release)
+
+	// Wait for the error state to clear so the next cadence decision is unambiguous.
+	deadline = time.Now().Add(2 * time.Second)
+	for {
+		errorCount, _, _ := manager.GetErrorState()
+		if errorCount == 0 {
+			break
+		}
+		if time.Now().After(deadline) {
+			t.Fatalf("error tracking never reset, errorCount=%d", errorCount)
+		}
+		time.Sleep(20 * time.Millisecond)
+	}
+
+	// The ticker is at 1s now. Wait for the next tick, where the loop must notice the
+	// recovery and restore the 3s cadence.
+	time.Sleep(1500 * time.Millisecond)
+	before := client.callCount()
+
+	// Observe a window that a 1s cadence would fill with scans and a 3s cadence would not.
+	const window = 5 * time.Second
+	time.Sleep(window)
+	scansInWindow := client.callCount() - before
+
+	// 3s cadence: at most 2 scans in 5s. 1s cadence: about 5.
+	if scansInWindow > 2 {
+		t.Errorf("scan loop ran %d scans in %v after recovering from a failed scan; "+
+			"the ticker was left at the %v backoff instead of returning to the configured %v",
+			scansInWindow, window, time.Second, baseInterval)
+	}
+	if scansInWindow == 0 {
+		t.Errorf("scan loop ran no scans in %v, expected the %v cadence to fire at least once", window, baseInterval)
+	}
+}
+
+// TestScanLoopEntersBackoffOnError checks the other half of the cadence logic: a failing
+// scan still has to shorten the ticker, so the fix above did not simply pin the loop to
+// the configured interval.
+func TestScanLoopEntersBackoffOnError(t *testing.T) {
+	config := DefaultMaintenanceConfig()
+	config.ScanIntervalSeconds = 600
+	manager := NewMaintenanceManager(nil, config, nil)
+
+	baseInterval := time.Duration(config.ScanIntervalSeconds) * time.Second
+
+	if got := manager.getScanInterval(baseInterval); got != baseInterval {
+		t.Errorf("healthy scan interval = %v, want the configured %v", got, baseInterval)
+	}
+
+	manager.mutex.Lock()
+	manager.errorCount = 1
+	manager.backoffDelay = time.Second
+	manager.mutex.Unlock()
+
+	if got := manager.getScanInterval(baseInterval); got != time.Second {
+		t.Errorf("scan interval while failing = %v, want the %v backoff", got, time.Second)
+	}
+
+	manager.mutex.Lock()
+	manager.resetErrorTracking()
+	manager.mutex.Unlock()
+
+	if got := manager.getScanInterval(baseInterval); got != baseInterval {
+		t.Errorf("scan interval after recovery = %v, want the configured %v", got, baseInterval)
+	}
+}
+
+// TestStopIsIdempotent guards the stop channel against a double close, which used to panic
+// when StopMaintenanceManager ran twice (for example on a shutdown path that also runs on
+// a signal handler).
+func TestStopIsIdempotent(t *testing.T) {
+	manager := NewMaintenanceManager(nil, DefaultMaintenanceConfig(), nil)
+
+	manager.mutex.Lock()
+	manager.running = true
+	manager.mutex.Unlock()
+
+	manager.Stop()
+	manager.Stop()
+
+	if manager.IsRunning() {
+		t.Error("manager still reports running after Stop")
+	}
+}
@@ -144,9 +144,14 @@ func DefaultMaintenanceConfig() *MaintenanceConfig {

 // Policy helper functions (since we can't add methods to type aliases)

-// GetTaskPolicy returns the policy for a specific task type
+// GetTaskPolicy returns the policy for a specific task type, or nil when the maintenance
+// policy has no entry for it.
+//
+// A nil maintenance policy is a legitimate state, not a programming error:
+// MaintenanceConfig.Policy is unset until something builds one, and UpdateConfig accepts a
+// config that carries none. Dereferencing it here panicked the whole admin process.
 func GetTaskPolicy(mp *MaintenancePolicy, taskType MaintenanceTaskType) *TaskPolicy {
-	if mp.TaskPolicies == nil {
+	if mp == nil || mp.TaskPolicies == nil {
 		return nil
 	}
 	return mp.TaskPolicies[string(taskType)]
@@ -174,6 +179,9 @@ func GetMaxConcurrent(mp *MaintenancePolicy, taskType MaintenanceTaskType) int {
 func GetRepeatInterval(mp *MaintenancePolicy, taskType MaintenanceTaskType) int {
 	policy := GetTaskPolicy(mp, taskType)
 	if policy == nil {
+		if mp == nil {
+			return 0
+		}
 		return int(mp.DefaultRepeatIntervalSeconds)
 	}
 	return int(policy.RepeatIntervalSeconds)
@@ -178,12 +178,25 @@ func LoadConfigFromPersistence(configPersistence interface{}) *Config {
 	if persistence, ok := configPersistence.(interface {
 		LoadBalanceTaskPolicy() (*worker_pb.TaskPolicy, error)
 	}); ok {
-		if policy, err := persistence.LoadBalanceTaskPolicy(); err == nil && policy != nil {
-			if err := config.FromTaskPolicy(policy); err == nil {
+		policy, err := persistence.LoadBalanceTaskPolicy()
+		switch {
+		case err != nil:
+			glog.Warningf("Could not read the persisted balance configuration, falling back to defaults: %v", err)
+		case policy == nil:
+			glog.V(1).Infof("No balance configuration persisted yet, using defaults")
+		default:
+			if err := config.FromTaskPolicy(policy); err != nil {
+				glog.Warningf("Could not apply the persisted balance configuration, falling back to defaults: %v", err)
+			} else {
 				glog.V(1).Infof("Loaded balance configuration from persistence")
 				return config
 			}
 		}
+	} else if configPersistence != nil {
+		// A store was handed in but does not expose the accessor, so the persisted
+		// settings are silently ignored - always a wiring bug, never a normal state.
+		glog.Warningf("%T cannot provide the persisted balance configuration: it has no LoadBalanceTaskPolicy() method, "+
+			"so the compiled-in defaults are used and any saved balance settings are ignored", configPersistence)
 	}

 	glog.V(1).Infof("Using default balance configuration")
@@ -42,6 +42,18 @@ func (d *GenericDetector) IsEnabled() bool {
 	return d.taskDef.Config.IsEnabled()
 }

+// SetEnabled turns detection for this task type on or off.
+//
+// The admin maintenance policy is applied to detectors through an
+// interface{ SetEnabled(bool) } type assertion (see
+// MaintenanceIntegration.configureDetectorFromPolicy). Every registered task is
+// backed by this generic detector, so without this method that assertion failed
+// for every task and the policy never reached the flag that
+// ScanWithTaskDetectors actually gates on. See issue #10874.
+func (d *GenericDetector) SetEnabled(enabled bool) {
+	d.taskDef.Config.SetEnabled(enabled)
+}
+
 // GenericScheduler implements TaskScheduler using function-based logic
 type GenericScheduler struct {
 	taskDef *TaskDefinition
@@ -127,3 +139,22 @@ func (s *GenericScheduler) GetDefaultRepeatInterval() time.Duration {
 func (s *GenericScheduler) IsEnabled() bool {
 	return s.taskDef.Config.IsEnabled()
 }
+
+// SetEnabled turns scheduling for this task type on or off. Detector and scheduler
+// share one TaskDefinition, so this is the same flag GenericDetector.SetEnabled sets;
+// both setters exist because the maintenance integration configures the two
+// independently. See GenericDetector.SetEnabled and issue #10874.
+func (s *GenericScheduler) SetEnabled(enabled bool) {
+	s.taskDef.Config.SetEnabled(enabled)
+}
+
+// SetMaxConcurrent applies the policy's concurrency limit for this task type. It is
+// the value GetMaxConcurrent returns, which the maintenance queue uses to decide
+// whether another task of this type may start. Non-positive limits are ignored
+// rather than turning into the implicit default of 1.
+func (s *GenericScheduler) SetMaxConcurrent(maxConcurrent int) {
+	if maxConcurrent <= 0 {
+		return
+	}
+	s.taskDef.MaxConcurrent = maxConcurrent
+}
@@ -241,12 +241,25 @@ func LoadConfigFromPersistence(configPersistence interface{}) *Config {
 	if persistence, ok := configPersistence.(interface {
 		LoadEcBalanceTaskPolicy() (*worker_pb.TaskPolicy, error)
 	}); ok {
-		if policy, err := persistence.LoadEcBalanceTaskPolicy(); err == nil && policy != nil {
-			if err := cfg.FromTaskPolicy(policy); err == nil {
+		policy, err := persistence.LoadEcBalanceTaskPolicy()
+		switch {
+		case err != nil:
+			glog.Warningf("Could not read the persisted EC balance configuration, falling back to defaults: %v", err)
+		case policy == nil:
+			glog.V(1).Infof("No EC balance configuration persisted yet, using defaults")
+		default:
+			if err := cfg.FromTaskPolicy(policy); err != nil {
+				glog.Warningf("Could not apply the persisted EC balance configuration, falling back to defaults: %v", err)
+			} else {
 				glog.V(1).Infof("Loaded EC balance configuration from persistence")
 				return cfg
 			}
 		}
+	} else if configPersistence != nil {
+		// A store was handed in but does not expose the accessor, so the persisted
+		// settings are silently ignored - always a wiring bug, never a normal state.
+		glog.Warningf("%T cannot provide the persisted EC balance configuration: it has no LoadEcBalanceTaskPolicy() method, "+
+			"so the compiled-in defaults are used and any saved EC balance settings are ignored", configPersistence)
 	}

 	glog.V(1).Infof("Using default EC balance configuration")
@@ -229,12 +229,25 @@ func LoadConfigFromPersistence(configPersistence interface{}) *Config {
 	if persistence, ok := configPersistence.(interface {
 		LoadErasureCodingTaskPolicy() (*worker_pb.TaskPolicy, error)
 	}); ok {
-		if policy, err := persistence.LoadErasureCodingTaskPolicy(); err == nil && policy != nil {
-			if err := config.FromTaskPolicy(policy); err == nil {
+		policy, err := persistence.LoadErasureCodingTaskPolicy()
+		switch {
+		case err != nil:
+			glog.Warningf("Could not read the persisted erasure coding configuration, falling back to defaults: %v", err)
+		case policy == nil:
+			glog.V(1).Infof("No erasure coding configuration persisted yet, using defaults")
+		default:
+			if err := config.FromTaskPolicy(policy); err != nil {
+				glog.Warningf("Could not apply the persisted erasure coding configuration, falling back to defaults: %v", err)
+			} else {
 				glog.V(1).Infof("Loaded erasure coding configuration from persistence")
 				return config
 			}
 		}
+	} else if configPersistence != nil {
+		// A store was handed in but does not expose the accessor, so the persisted
+		// settings are silently ignored - always a wiring bug, never a normal state.
+		glog.Warningf("%T cannot provide the persisted erasure coding configuration: it has no LoadErasureCodingTaskPolicy() method, "+
+			"so the compiled-in defaults are used and any saved erasure coding settings are ignored", configPersistence)
 	}

 	glog.V(1).Infof("Using default erasure coding configuration")
@@ -73,12 +73,25 @@ func LoadConfigFromPersistence(configPersistence interface{}) *Config {
 	if persistence, ok := configPersistence.(interface {
 		LoadVacuumTaskPolicy() (*worker_pb.TaskPolicy, error)
 	}); ok {
-		if policy, err := persistence.LoadVacuumTaskPolicy(); err == nil && policy != nil {
-			if err := config.FromTaskPolicy(policy); err == nil {
+		policy, err := persistence.LoadVacuumTaskPolicy()
+		switch {
+		case err != nil:
+			glog.Warningf("Could not read the persisted vacuum configuration, falling back to defaults: %v", err)
+		case policy == nil:
+			glog.V(1).Infof("No vacuum configuration persisted yet, using defaults")
+		default:
+			if err := config.FromTaskPolicy(policy); err != nil {
+				glog.Warningf("Could not apply the persisted vacuum configuration, falling back to defaults: %v", err)
+			} else {
 				glog.V(1).Infof("Loaded vacuum configuration from persistence")
 				return config
 			}
 		}
+	} else if configPersistence != nil {
+		// A store was handed in but does not expose the accessor, so the persisted
+		// settings are silently ignored - always a wiring bug, never a normal state.
+		glog.Warningf("%T cannot provide the persisted vacuum configuration: it has no LoadVacuumTaskPolicy() method, "+
+			"so the compiled-in defaults are used and any saved vacuum settings are ignored", configPersistence)
 	}

 	glog.V(1).Infof("Using default vacuum configuration")
@@ -0,0 +1,75 @@
+package vacuum
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/worker_pb"
+)
+
+type stubVacuumStore struct {
+	policy *worker_pb.TaskPolicy
+	err    error
+}
+
+func (s *stubVacuumStore) LoadVacuumTaskPolicy() (*worker_pb.TaskPolicy, error) {
+	return s.policy, s.err
+}
+
+// wrongShapedStore is what the maintenance manager used to be handed: a non-nil value that
+// does not satisfy the accessor the loader asserts on. It has to keep falling back to the
+// defaults, but no longer silently - the reporter of issue #10874 had to read the source to
+// find out why their disabled task kept running.
+type wrongShapedStore struct{}
+
+func (wrongShapedStore) SomethingElse() {}
+
+func TestLoadConfigFromPersistenceUsesPersistedPolicy(t *testing.T) {
+	persisted := NewDefaultConfig()
+	persisted.Enabled = false
+	persisted.GarbageThreshold = 0.75
+	persisted.MaxConcurrent = 5
+
+	loaded := LoadConfigFromPersistence(&stubVacuumStore{policy: persisted.ToTaskPolicy()})
+	if loaded == nil {
+		t.Fatal("LoadConfigFromPersistence returned nil")
+	}
+	if loaded.Enabled {
+		t.Error("enabled = true, want the persisted false")
+	}
+	if loaded.GarbageThreshold != 0.75 {
+		t.Errorf("garbage threshold = %v, want the persisted 0.75", loaded.GarbageThreshold)
+	}
+	if loaded.MaxConcurrent != 5 {
+		t.Errorf("max concurrent = %d, want the persisted 5", loaded.MaxConcurrent)
+	}
+}
+
+func TestLoadConfigFromPersistenceFallsBackToDefaults(t *testing.T) {
+	defaults := NewDefaultConfig()
+
+	cases := map[string]interface{}{
+		"no store configured":     nil,
+		"store without the value": &stubVacuumStore{},
+		"store that errors":       &stubVacuumStore{err: errors.New("disk on fire")},
+		"store of the wrong type": wrongShapedStore{},
+	}
+
+	for name, store := range cases {
+		t.Run(name, func(t *testing.T) {
+			loaded := LoadConfigFromPersistence(store)
+			if loaded == nil {
+				t.Fatal("LoadConfigFromPersistence returned nil")
+			}
+			if !loaded.Enabled {
+				t.Error("enabled = false, want the compiled-in default true")
+			}
+			if loaded.GarbageThreshold != defaults.GarbageThreshold {
+				t.Errorf("garbage threshold = %v, want the default %v", loaded.GarbageThreshold, defaults.GarbageThreshold)
+			}
+			if loaded.ScanIntervalSeconds != defaults.ScanIntervalSeconds {
+				t.Errorf("scan interval = %d, want the default %d", loaded.ScanIntervalSeconds, defaults.ScanIntervalSeconds)
+			}
+		})
+	}
+}