Consider preventing store corruption by default #531

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opened 2024-09-24 07:21:56 +00:00 by sersorrel · 1 comment

sersorrel commented

2024-09-24 07:21:56 +00:00

If the system shuts down uncleanly, it's possible to corrupt the contents of /nix/store (e.g. ending up with zero-length .nix files, which invariably cause eval errors).

Describe the solution you'd like

I'd like Lix to support the fsync-store-paths option (see https://github.com/NixOS/nix/pull/7126), which I suspect was merged into Nix after Lix was forked off.

I'd also like the note in that PR whereby "Local builds can still result in non-fsynced writes to the nix store." to be addressed somehow.

Describe alternatives you've considered

I could enable sync-before-registering, but this apparently (I have not yet verified) has a large performance impact.

I believe Lix should, in the interests of correctness, default to whatever behaviour will avoid store corruption on unclean shutdown.

Additional context

## Is your feature request related to a problem? Please describe. If the system shuts down uncleanly, it's possible to corrupt the contents of /nix/store (e.g. ending up with zero-length .nix files, which invariably cause eval errors). ## Describe the solution you'd like I'd like Lix to support the fsync-store-paths option (see https://github.com/NixOS/nix/pull/7126), which I suspect was merged into Nix after Lix was forked off. I'd also like the note in that PR whereby "Local builds can still result in non-fsynced writes to the nix store." to be addressed somehow. ## Describe alternatives you've considered I could enable sync-before-registering, but this apparently (I have not yet verified) has a large performance impact. I believe Lix should, in the interests of correctness, default to whatever behaviour will avoid store corruption on unclean shutdown. ## Additional context

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