Re: GC hints

[Alex Kost <alezost@gmail.com>]

Mark H Weaver (2018-12-20 07:12 -0500) wrote:

> Hi Ludovic,
>
> Ludovic Courtès <ludo@gnu.org> writes:
>
>> Actually, I was also wondering whether we should provide a configurable
>> mechanism that would, by default, automatically delete old GC roots and
>> maybe even run the GC automatically when needed—similar to what Git
>> does.
>>
>> Thoughts?
>
> I think it's reasonable to automatically run GC by default, but I would
> strongly advise against deleting GC roots automatically by default
> without the user's knowledge and consent.
>
> It's certainly true that git performs GC automatically, but does it
> automatically delete GC roots by default?  I've never seen it do this,
> and I would be surprised and angry if it did.
>
> I consider Guix GC roots to be potentially valuable user data,
> regardless of age.  For example, an old GC root might be valuable
> because it was used to perform an experiment that should be repeatable,
> or because it is known to work reliably for a given job, and newer
> versions have not yet been tested.
>
> I, for one, expect my old profiles, system generations, and other GC
> roots to be kept unless I explicitly delete them, and I suspect I'm not
> alone.  If I hadn't been paying close attention to Guix development, and
> later discovered that Guix had deleted my GC roots without my consent, I
> would be surprised and angry.

You are not alone!  I completely agree with your points.

-- 
Alex