Auto‑Save Recovery Limits: Selecting the Correct File When Multiple Auto‑Saves Share Modification Time

Question

Auto‑Save Recovery Limits
Blender’s Auto‑Save system creates temporary files in the same directory as the active .blend file, prefixed with a tilde and suffixed by a timestamp. When Blender crashes, the Recovery dialog offers the user a file to restore. The selection algorithm, however, relies solely on the file’s modification time, ignoring the embedded timestamp in the filename. If two or more auto‑save files have identical modification times—due to file‑system clock precision, manual copying, or network share quirks—Blender may present an ambiguous choice or default to the first file found. This behavior can lead to inadvertent data loss, especially in shared project directories where multiple auto‑saves accumulate.

The unresolved question is whether Blender’s recovery logic can be configured to consider the embedded timestamp, or if a future release might offer a per‑scene or per‑file custom directory for auto‑saves to mitigate clutter and ambiguity.

Which file does Blender actually offer when multiple auto‑save files share the same modification timestamp?
Does Blender provide any option to prioritize the embedded timestamp over the file modification time during recovery?

Tasadduq Burney · Answer

Answer
When two or more auto‑save files have identical modification timestamps, Blender’s recovery dialog presents the file that comes first in the directory listing – effectively the one with the lowest lexical name (e.g., ~MyScene.001.blend before ~MyScene.002.blend).
Confirmed facts

Blender’s auto‑save recovery code (WM_auto_save_recover) sorts candidates solely by stat().st_mtime; the numeric timestamp embedded in the filename is never consulted.
As of Blender 4.0 and earlier, there is no user‑visible preference to change this behaviour or to prioritize the embedded timestamp.
The behaviour is identical on Windows, macOS and Linux because it relies on the C runtime’s directory enumeration order when modification times are equal.

Steps to verify the selection

Locate the auto‑save folder (same directory as the active .blend file).
List the files; note their names and modification times (e.g., ls -l on Linux/macOS or dir on Windows).
If two files show the same timestamp, the one that appears first alphabetically will be offered in the recovery dialog after a crash.
To test, copy an existing auto‑save file and use touch -r original copy (or Copy-Item with -Attributes on PowerShell) to give the copy the exact same modification timestamp, then restart Blender and observe the recovery choice.

Missing diagnostic detail
If you observe that Blender does not follow the lexical‑order rule, please confirm whether the file‑system actually reports identical st_mtime values (nanosecond precision may differ) and share the exact output of stat for the conflicting files.

Auto‑Save Recovery Limits: Selecting the Correct File When Multiple Auto‑Saves Share Modification Time

Auto‑Save Recovery Limits

1 answer

Answer

Confirmed facts

Steps to verify the selection

Missing diagnostic detail

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