worker: overpay (migration) downloads on low health slabs

api/autopilot.go

@@ -139,6 +139,10 @@ func (sb HostScoreBreakdown) String() string {
 	return fmt.Sprintf("Age: %v, Col: %v, Int: %v, SR: %v, UT: %v, V: %v, Pr: %v", sb.Age, sb.Collateral, sb.Interactions, sb.StorageRemaining, sb.Uptime, sb.Version, sb.Prices)
 }
 
+func (hgb HostGougingBreakdown) DownloadGouging() bool {
+	return hgb.V3.DownloadErr != ""
+}
+
 func (hgb HostGougingBreakdown) Gouging() bool {
 	return hgb.V2.Gouging() || hgb.V3.Gouging()
 }

api/settings.go

@@ -64,6 +64,12 @@ type (
 		// MinMaxEphemeralAccountBalance is the minimum accepted value for
 		// `MaxEphemeralAccountBalance` in the host's price settings.
 		MinMaxEphemeralAccountBalance types.Currency `json:"minMaxEphemeralAccountBalance"`
+
+		// MigrationSurchargeMultiplier is the multiplier applied to the
+		// 'MaxDownloadPrice' when checking whether a host is too expensive,
+		// this multiplier is only applied for when trying to migrate critically
+		// low-health slabs.
+		MigrationSurchargeMultiplier uint64 `json:"migrationSurchargeMultiplier"`
 	}
 
 	// RedundancySettings contain settings that dictate an object's redundancy.

api/worker.go

@@ -21,10 +21,6 @@ var (
 	// ErrContractSetNotSpecified is returned by the worker API by endpoints that
 	// need a contract set to be able to upload data.
 	ErrContractSetNotSpecified = errors.New("contract set is not specified")
-
-	// ErrGougingPreventedDownload is returned by the worker API when a download
-	// failed because a critical number of hosts were price gouging.
-	ErrGougingPreventedDownload = errors.New("gouging settings prevented download from succeeding")
 )
 
 type (

autopilot/alerts.go

@@ -141,11 +141,6 @@ func newSlabMigrationFailedAlert(slabKey object.EncryptionKey, health float64, e
 		severity = alerts.SeverityCritical
 	}
 
-	hint := "Migration failures can be temporary, but if they persist it can eventually lead to data loss and should therefor be taken very seriously."
-	if isErr(err, api.ErrGougingPreventedDownload) {
-		hint += " In this particular case, one or more hosts were considered to be price gouging. It might be necessary to adjust your price gouging settings."
-	}
-
 	return alerts.Alert{
 		ID:       alertIDForSlab(alertMigrationID, slabKey),
 		Severity: severity,
@@ -154,7 +149,7 @@ func newSlabMigrationFailedAlert(slabKey object.EncryptionKey, health float64, e
 			"error":   err,
 			"health":  health,
 			"slabKey": slabKey.String(),
-			"hint":    hint,
+			"hint":    "Migration failures can be temporary, but if they persist it can eventually lead to data loss and should therefor be taken very seriously.",
 		},
 		Timestamp: time.Now(),
 	}