Ludovic Courtès <ludo@gnu.org> writes:
> The error message that’s haunting us:
>
>   opening file `/gnu/store/….drv': No such file or directory
>
> comes from guix-daemon.  It happens while the client is doing an
> ‘add-text-to-store’ RPC to add that .drv to the store.
> ‘LocalStore::addTextToStore’ supposedly creates the .drv file in
> /gnu/store and then reads it back (‘registerValidPath’ -> ‘addValidPath’
> -> ‘readDerivation’ -> ‘readFile’): this is where it gets ENOENT.
>
> It would suggest that the database is consistent, but that somehow
> writes don’t go through the overlay FS.

Most interesting.

I saw a comment
> void LocalStore::registerValidPaths(const ValidPathInfos & infos)
> {
>     /* SQLite will fsync by default, but the new valid paths may not be fsync-ed.
>      * So some may want to fsync them before registering the validity, at the
>      * expense of some speed of the path registering operation. */
>     if (settings.syncBeforeRegistering) sync();

In vain, I therefore tried