bug#50353: Excessive temproots size when running guix build

[Ludovic Courtès]

Hi,

Christopher Baines <mail@cbaines.net> skribis:

> I spotted a problem with data.guix.gnu.org trying to process this old
> revision [1]
>
> 1: https://data.guix.gnu.org/revision/75dabac633bb9a33efbebf859f8aa4bb3b9582b2
>
> The machine ran out of disk space, as a ~30GiB file had been created in
> /var/guix/temproots.

Sounds fishy.  Those files contain a nul-separated list of GC roots
(store file names).  Thus, a file in there is proportional to the number
of ‘add-temp-root’ RPCs made by the client during the session.

A client with a long-running session (‘guix publish’, Coordinator, Data
Service, Cuirass, etc.) that regularly adds temp roots makes that file
grow endlessly.

HTH!

Ludo’.