StationAutoSave

How the autosave timer works, what gates a fire, and why a fresh -new dedicated-server world logs Save Failed: Folder name is empty. every interval instead of autosaving.

Timer architecture: wall-clock, not game time

StationAutoSave (static class, 0.2.6403.27689 client decompile line 267571) schedules with a System.Timers.Timer, so the countdown runs on WALL-CLOCK time. Time.timeScale = 0 (a paused world, or a tool freezing the sun) does not slow or stop the schedule; pause is only consulted at fire time (next section).

    public static class StationAutoSave
    {
        private static readonly System.Timers.Timer _autoSaveTimer = new System.Timers.Timer();

        private static async void TimerElapsed(object sender, ElapsedEventArgs e)
        {
            await UniTask.SwitchToMainThread();
            AutoSaveNow();
        }

Timer.Elapsed fires on a ThreadPool thread; the handler marshals to the main thread through the UniTask player loop, which runs on a headless server even while the game tick is parked (see SimulationTickDriverHooks.md).

ResetAutoSave() (line 267592) stops the timer and, when Settings.CurrentData.AutoSave && !GameManager.IsTutorial && !GameManager.IsNewTutorial, restarts it with Interval = Settings.CurrentData.SaveInterval * 1000. In batch mode it prints the Auto save stopped / Auto save started (<interval>) console lines. Every call restarts the countdown from zero; it is called from GameManager.StartGame, World.NewAsync, and the load paths, so back-to-back stopped/started pairs at world start are normal.

Gates at fire time

        private static void AutoSaveNow()
        {
            if (!GameManager.IsTutorial && !GameManager.IsNewTutorial && !WorldManager.IsGamePaused && GameManager.GameState == GameState.Running && !Assets.Scripts.Networking.NetworkManager.IsClient)
            {
                AutoSaveTask().Forget();
            }
        }

A PAUSED world silently skips the autosave (no log line at all): the timer keeps running, the fire is discarded. Diagnostic consequence: on a headless server, ANY autosave-attempt line at the interval mark (success or failure) is positive evidence the world was unpaused and Running at that moment.

AutoSaveTask awaits SaveHelper.AutoSave(XmlSaveLoad.Instance.CurrentStationName, ...) and prints the SaveResult message on failure via ConsoleWindow.PrintError.

Fresh -new worlds cannot autosave: empty station name

On a dedicated server started with -new <Map>, XmlSaveLoad.Instance.CurrentStationName is empty until a first named save assigns one. The autosave then fails name validation before any save work starts, and the server logs, every SaveInterval seconds:

15:08:24: Save Failed: Folder name is empty.

(verbatim from a 2026-07-02 dedicated-server run at 0.2.6403.27689; world created 15:03:24, SaveInterval 300, failure logged exactly at +300 s). The failure happens before SaveHelper.PrepareToSave, so PauseGameTick is never called and the simulation is not disturbed: an InspectorPlus PauseGameTick tracer recorded zero calls across the interval.

Consequences:

• A -new world produces NO real autosaves until it gets a name. The stdin console save "<name>" path would assign one, but stdin console commands are a no-op on the batch-mode dedicated server (observed at 0.2.6228.27061 and re-confirmed at 0.2.6403.27689: save queued via the launcher control file produced no save folder, no log response). Starting with -load <SaveName> instead gives the world a name from the start and autosaves work normally.
• When a test plan uses "an AutoSave line" as the world-is-ticking readiness marker (DedicatedServer/CLAUDE.md, "First-autosave grep"), on a -new world watch for the Save Failed: Folder name is empty. line instead; it is emitted at the same cadence and implies the same unpaused-and-running state.

Verification history

• 2026-07-02: page created during the headless-tick investigation. Timer/gate code quoted verbatim from the 0.2.6403.27689 client decompile (lines 267571-267633); the empty-folder failure and its exact +interval timing observed live on the dedicated server the same day. The "stdin save no-op" cross-check is the launcher -Save command timing out with no Saved line and no folder appearing under data/saves/.

Open questions

• Which code path assigns CurrentStationName on the dedicated server besides -load (for example, whether the first client-driven manual save or an admin serverrun save sets it). Not needed for current test flows; -load covers them.