Subject: bug#62656: broken guix time-machine + software-heritage

From: Ludovic Courtès <[email-masked]>
Date: Thu, 04 May 2023 15:05:44 +0200

Hi,

Simon Tournier <[email-masked]> skribis:

> On Thu, 4 May 2023 at 09:22, Ludovic Courtès <[email-masked]> wrote:
>
>> > Even if the bug on SWH would be fixed, at the rate the Guix repo is
>> > growing, it would be impractical to cook the whole Guix repo.
>>
>> Falling back to SWH to fetch channels is something we expect to be rare,
>> though.
>
> Being rare will not make it practical. ;-)
>
> What I am trying to point is that considering the size of the Guix
> repository and its rate, the current implementation will not scale and
> the fallback will be impossible for the end-user.

It’s not impossible, it just takes time (how long exactly, I don’t know,
we should check with the SWH folks what we can expect and what the
relevant factors are.)

That it takes time is acceptable IMO: we’re likely talking about
disaster recovery after the Savannah repo and its GitHub mirror have
disappeared.

Other channels, are typically smaller but also more likely to vanish; I
wonder how that affects the cooking time at SWH—again something to ask
them.

>> > And it appears to me weird when we, most of the time, need a very
>> > restricted set of commits.
>> >
>> > We could imagine to locally create a new repo (git init) and only add
>> > the content of the commit specified by “guix time-machine”.
>>
>> To do that we’d need to say goodbye to the features I mentioned above.
>
> Well, I do not see which features will be missing.

Those mentioned earlier, provenance tracking and downgrade detection in
particular.

Ludo’.