Reuse cached scores on nodes with another st_dev

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Changelog
 
+## Unreleased
+
+### Fixed
+- Per-run CSV and PAE plot reuse no longer depend on the device number of the files. A shared filesystem such as BeeGFS reports another `st_dev` for the same file on each cluster node, so a recursive run on one node recomputed every table and redrew every plot certified on another. Size, mtime, ctime and inode still detect edits and replaced files. Manifests written by 1.4.4 are recomputed once, as after any software change.
+
 ## 1.4.4 - 2026-10-01
 
 ### Fixed

src/alphajudge/cache.py

@@ -49,10 +49,12 @@ def file_fingerprint(path: Path) -> dict[str, int]:
 
     ctime supplements mtime, but coarse/preserved timestamps can still hide
     same-size rewrites. Use content validation when metadata is insufficient.
+    The device number is not part of it: a shared filesystem (BeeGFS) reports
+    another st_dev for the same file on each cluster node.
     """
     stat = path.stat()
     return {"size": stat.st_size, "mtime_ns": stat.st_mtime_ns, "ctime_ns": stat.st_ctime_ns,
-            "device": stat.st_dev, "inode": stat.st_ino}
+            "inode": stat.st_ino}
 
 
 def software_identity() -> dict:

test/test_run_integrity.py

@@ -9,6 +9,7 @@
 import shutil
 from dataclasses import replace
 from pathlib import Path
+from types import SimpleNamespace
 
 import numpy as np
 import pytest
@@ -232,6 +233,24 @@ def test_cache_detects_added_removed_and_replaced_inputs(af2_run):
     assert cache.request_identity(directory, csv_path) != before
 
 
+def test_cache_and_plots_are_reused_on_a_node_with_another_device_number(af2_run, record_process, monkeypatch):
+    directory, _ = af2_run
+    score(directory, skip_pae_png=False)
+    calls = record_process()
+    stat = Path.stat
+    def on_another_node(self, **kwargs):
+        fields = {name: getattr(stat(self, **kwargs), name)
+                  for name in dir(os.stat_result) if name.startswith("st_")}
+        fields["st_dev"] += 1
+        return SimpleNamespace(**fields)
+    def redraw(*args, **kwargs):
+        pytest.fail("A current PAE plot was redrawn")
+    monkeypatch.setattr(Path, "stat", on_another_node)
+    monkeypatch.setattr(AF2Parser, "parse_run", redraw)
+    score(directory, skip_pae_png=False)
+    assert calls == []
+
+
 def test_png_toggle_generates_missing_plot_without_rescoring(af2_run, monkeypatch):
     directory, models = af2_run
     original = score(directory)