forked from
anil.recoil.org/monopam-myspace
My aggregated monorepo of OCaml code, automaintained
Always use cp merge instead of overlayfs multi-lower for dep stacking
overlayfs multi-lower does NOT merge directories across layers — only
the topmost layer's version of a directory is visible. This broke
packages depending on multiple conf packages that install into the
same system directories (e.g. /usr/include/GL/).
Now always uses Stack.merge (cp --archive --link --no-target-directory)
to combine all dep layers into a single lower dir, like day10 does.
Hard links mean no extra disk space. Files from all layers are visible
in the same directory tree.
Fixes lablgl.1.05 and likely many other failures involving
conf-* packages.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
+7
-13
+7
-13
day11/build/run_in_layers.ml
+7
-13
day11/build/run_in_layers.ml
···
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let merged = Fpath.(temp_dir / "merged") in
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let lower = Fpath.(temp_dir / "lower") in
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List.iter mkdir [ upper; work; merged ];
57
-
(* Use overlayfs multi-lower when possible (zero copy, instant).
58
-
Fall back to cp-merge when there are too many layers — the mount
59
-
options string is limited to one page (4096 bytes). *)
60
-
let all_layer_fs_dirs = List.filter_map (fun dir ->
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-
let fs = Fpath.(dir / "fs") in
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-
if Bos.OS.Dir.exists fs |> Result.get_ok then Some fs else None
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-
) build_dirs in
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-
let lowerdir_len = List.fold_left (fun acc fs ->
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-
acc + String.length (Fpath.to_string fs) + 1
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-
) 0 (all_layer_fs_dirs @ [ base_fs ]) in
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-
let use_merge = lowerdir_len > 3500 in
57
+
(* Merge all dep layers into a single lower dir using cp --link.
58
+
overlayfs multi-lower does NOT merge directories across layers —
59
+
only the topmost layer's version of a directory is visible. This
60
+
broke packages depending on multiple conf packages that install
61
+
into the same system directories (e.g. /usr/include/GL/). *)
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let layer_fs_dirs =
69
-
if not use_merge then all_layer_fs_dirs
63
+
if build_dirs = [] then []
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64
else begin
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mkdir lower;
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let merge_result =
···
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end
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in
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let cleanup_internals () =
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-
if use_merge then
79
+
if build_dirs <> [] then
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ignore (Day11_exec.Sudo.rm_rf env lower);
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ignore (Day11_exec.Sudo.rm_rf env work);
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ignore (Day11_exec.Sudo.rm_rf env merged);