fix: increase default delete retention to 15 months (#10252)

365 + 90 days = 10920h.

Also, actually enforce the minimum interval of 24h.

internal/db/sqlite/db_open.go

@@ -17,14 +17,17 @@ import (
 	"github.com/syncthing/syncthing/internal/slogutil"
 )
 
-const maxDBConns = 16
+const (
+	maxDBConns         = 16
+	minDeleteRetention = 24 * time.Hour
+)
 
 type DB struct {
+	*baseDB
+
 	pathBase        string
 	deleteRetention time.Duration
 
-	*baseDB
-
 	folderDBsMut   sync.RWMutex
 	folderDBs      map[string]*folderDB
 	folderDBOpener func(folder, path string, deleteRetention time.Duration) (*folderDB, error)
@@ -36,7 +39,11 @@ type Option func(*DB)
 
 func WithDeleteRetention(d time.Duration) Option {
 	return func(s *DB) {
-		s.deleteRetention = d
+		if d <= 0 {
+			s.deleteRetention = 0
+		} else {
+			s.deleteRetention = max(d, minDeleteRetention)
+		}
 	}
 }
 

internal/db/sqlite/db_service.go

@@ -19,10 +19,8 @@ import (
 )
 
 const (
-	internalMetaPrefix     = "dbsvc"
-	lastMaintKey           = "lastMaint"
-	defaultDeleteRetention = 180 * 24 * time.Hour
-	minDeleteRetention     = 24 * time.Hour
+	internalMetaPrefix = "dbsvc"
+	lastMaintKey       = "lastMaint"
 )
 
 func (s *DB) Service(maintenanceInterval time.Duration) suture.Service {