Refactored enum and messages. Also added 9p to the list since mono misclassifies it.

src/NzbDrone.Api/Config/HostConfigResource.cs

@@ -20,7 +20,6 @@ namespace NzbDrone.Api.Config
         public string Password { get; set; }
         public string LogLevel { get; set; }
         public string ConsoleLogLevel { get; set; }
-        public DatabaseJournalType DatabaseJournalMode { get; set; }
         public string Branch { get; set; }
         public string ApiKey { get; set; }
         public string SslCertHash { get; set; }

src/NzbDrone.Core/Configuration/ConfigFileProvider.cs

@@ -185,7 +185,7 @@ namespace NzbDrone.Core.Configuration
         public string LogLevel => GetValue("LogLevel", "Info");
         public string ConsoleLogLevel => GetValue("ConsoleLogLevel", string.Empty, persist: false);
 
-        public DatabaseJournalType DatabaseJournalMode => GetValueEnum("DatabaseJournalMode", DatabaseJournalType.Wal, persist: false);
+        public DatabaseJournalType DatabaseJournalMode => GetValueEnum("DatabaseJournalMode", DatabaseJournalType.Auto, persist: false);
 
         public string SslCertHash => GetValue("SslCertHash", "");
 

src/NzbDrone.Core/Datastore/ConnectionStringFactory.cs

@@ -52,7 +52,7 @@ namespace NzbDrone.Core.Datastore
 
             connectionBuilder.JournalMode = GetJournalMode(dbPath);
 
-            if (connectionBuilder.JournalMode == SQLiteJournalModeEnum.Truncate)
+            if (OsInfo.IsOsx)
             {
                 connectionBuilder.Add("Full FSync", true);
             }
@@ -65,26 +65,36 @@ namespace NzbDrone.Core.Datastore
 
         private SQLiteJournalModeEnum GetJournalMode(string path)
         {
-            var driveType = _diskProvider.GetMount(path).DriveType;
+            if (_configFileProvider.DatabaseJournalMode != DatabaseJournalType.Auto)
-
-            if (driveType == DriveType.Network || driveType == DriveType.Unknown)
             {
-                _logger.Debug("Network filesystem store for application data detected, disabling WAL mode for SQLite");
+                _logger.Debug("Database journal mode overridden by config.xml, using {0} journal mode", _configFileProvider.DatabaseJournalMode);
-                return SQLiteJournalModeEnum.Truncate;
+                return (SQLiteJournalModeEnum)_configFileProvider.DatabaseJournalMode;
-            }
-
-            if (_configFileProvider.DatabaseJournalMode != (DatabaseJournalType)SQLiteJournalModeEnum.Wal)
-            {
-                _logger.Debug("DatabaseJournalMode tag detected in config.xml, disabling WAL mode for SQLite");
-                return SQLiteJournalModeEnum.Truncate;
             }
 
             if (OsInfo.IsOsx)
             {
-                _logger.Debug("macOS operating system detected, disabling WAL mode for SQLite");
+                _logger.Debug("macOS operating system, using Truncate database journal mode");
                 return SQLiteJournalModeEnum.Truncate;
             }
 
+            var mount = _diskProvider.GetMount(path);
+
+            if (mount == null)
+            {
+                _logger.Debug("Database {0} located on unknown filesystem, using Truncate journal mode", path);
+                return SQLiteJournalModeEnum.Truncate;
+            }
+
+            if (mount.DriveType == DriveType.Network || mount.DriveType == DriveType.Unknown)
+            {
+                _logger.Debug("Database {0} located on filesystem {1} with type {2}, using Truncate journal mode", path, mount.DriveFormat, mount.DriveType);
+                return SQLiteJournalModeEnum.Truncate;
+            }
+            else
+            {
+                _logger.Debug("Database {0} located on filesystem {1} with type {2}, using WAL journal mode", path, mount.DriveFormat, mount.DriveType);
+            }
+
             return SQLiteJournalModeEnum.Wal;
         }
     }

src/NzbDrone.Core/Datastore/DatabaseJournalType.cs

@@ -4,7 +4,9 @@ namespace NzbDrone.Core.Datastore
 {
     public enum DatabaseJournalType
     {
+        Auto = SQLiteJournalModeEnum.Default,
         Wal = SQLiteJournalModeEnum.Wal,
-        Truncate = SQLiteJournalModeEnum.Truncate
+        Truncate = SQLiteJournalModeEnum.Truncate,
+        Delete = SQLiteJournalModeEnum.Delete
     }
 }

src/NzbDrone.Core/NzbDrone.Core.csproj

@@ -136,6 +136,7 @@
     <Compile Include="Configuration\InvalidConfigFileException.cs" />
     <Compile Include="Configuration\RescanAfterRefreshType.cs" />
     <Compile Include="Configuration\ResetApiKeyCommand.cs" />
+    <Compile Include="Datastore\DatabaseJournalType.cs" />
     <Compile Include="Datastore\Migration\134_add_specials_folder_format.cs" />
     <Compile Include="Datastore\Migration\132_add_download_client_priority.cs" />
     <Compile Include="Datastore\Migration\131_download_propers_config.cs" />

src/NzbDrone.Mono/Disk/ProcMountProvider.cs

@@ -17,7 +17,7 @@ namespace NzbDrone.Mono.Disk
     public class ProcMountProvider : IProcMountProvider
     {
         private static string[] _fixedTypes = new [] { "ext3", "ext2", "ext4", "vfat", "fuseblk", "xfs", "jfs", "msdos", "ntfs", "minix", "hfs", "hfsplus", "qnx4", "ufs", "btrfs" };
-        private static string[] _networkDriveTypes = new [] { "cifs", "nfs", "nfs4", "nfsd", "sshfs" };
+        private static string[] _networkDriveTypes = new [] { "cifs", "nfs", "nfs4", "nfsd", "sshfs", "9p" };
         private static readonly Regex OctalRegex = new Regex(@"\\\d{3}", RegexOptions.Compiled);
 
         private const string PROC_MOUNTS_FILENAME = @"/proc/mounts";