audit store gc code #206

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opened 2024-04-01 23:59:28 +00:00 by pennae · 2 comments

pennae commented

2024-04-01 23:59:28 +00:00

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the store gc code is known for deleting more than it should[citation needed], and in any case probably does not implement proper mark&sweep scanning (either not correctly, or not at all). doing this properly without risking collecting too much probably needs hooking into fsnotify, temporarily enabling atime, or other such fun things.

the store gc code is known for deleting more than it should\[citation needed], and in any case probably does not implement proper mark&sweep scanning (either not correctly, or not at all). doing this properly without risking collecting too much probably needs hooking into fsnotify, temporarily enabling atime, or other such fun things.

gabriella439 commented

2024-04-02 16:15:00 +00:00

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I also sometimes have the opposite problem where it's not deleting enough. In other words, even when I remove all the relevant GC roots for a path it still won't get deleted even if nix-store --gc --print-roots ${PATH_I_WANT_TO_DELETE} produces an empty output.

I also sometimes have the opposite problem where it's not deleting enough. In other words, even when I remove all the relevant GC roots for a path it still won't get deleted even if `nix-store --gc --print-roots ${PATH_I_WANT_TO_DELETE}` produces an empty output.

pennae commented

2024-04-02 16:16:49 +00:00

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that's a somewhat related but entirely different problem. hopefully that can be solved by not using an sqlite database as the ground source of truth on path liveness when the paths themseleves are right there. (we should be using xattrs or similar instead to store this kind of metadata and use the sqlite db only as cache.)

that's a somewhat related but entirely different problem. hopefully *that* can be solved by not using an sqlite database as the ground source of truth on path liveness when the paths themseleves are *right there*. (we should be using xattrs or similar instead to store this kind of metadata and use the sqlite db only as cache.)