From: "Ludovic Courtès" <ludo@gnu.org>
To: zimoun <zimon.toutoune@gmail.com>
Cc: 42162@debbugs.gnu.org, "Maurice Brémond" <Maurice.Bremond@inria.fr>
Subject: bug#42162: Recovering source tarballs
Date: Tue, 21 Jul 2020 23:22:00 +0200 [thread overview]
Message-ID: <87k0ywlg1z.fsf@gnu.org> (raw)
In-Reply-To: <CAJ3okZ0iMNjv93MM1FkEB3_zXA48Rq3rKXhwwug85fNRRc41Mg@mail.gmail.com> (zimoun's message of "Mon, 20 Jul 2020 17:52:09 +0200")
Hi!
zimoun <zimon.toutoune@gmail.com> skribis:
> On Mon, 20 Jul 2020 at 10:39, Ludovic Courtès <ludo@gnu.org> wrote:
>> zimoun <zimon.toutoune@gmail.com> skribis:
>> > On Sat, 11 Jul 2020 at 17:50, Ludovic Courtès <ludo@gnu.org> wrote:
>
>> There are many many comments in your message, so I took the liberty to
>> reply only to the essence of it. :-)
>
> Many comments because many open topics. ;-)
Understood, and they’re very valuable but (1) I choose not to just do
email :-), and (2) I like to separate issues in reasonable chunks rather
than long threads addressing all the problems we’ll have to deal with.
I think it really helps keep things tractable!
>> Lookup issue. :-) The hash in a CID is not just a raw blob hash.
>> Files are typically chunked beforehand, assembled as a Merkle tree, and
>> the CID is roughly the hash to the tree root. So it would seem we can’t
>> use IPFS as-is for tarballs.
>
> Using the Git-repo map/table, then it becomes an option, right?
> Well, SWH would be a backend and IPFS could be another one. Or any
> "cloudy" storage system that could appear in the future, right?
Sure, why not.
>> >> • If we no longer deal with tarballs but upstreams keep signing
>> >> tarballs (not raw directory hashes), how can we authenticate our
>> >> code after the fact?
>> >
>> > Does Guix automatically authenticate code using signed tarballs?
>>
>> Not automatically; packagers are supposed to authenticate code when they
>> add a package (‘guix refresh -u’ does that automatically).
>
> So I miss the point of having this authentication information in the
> future where upstream has disappeared.
What I meant above, is that often, what we have is things like detached
signatures of raw tarballs, or documents referring to a tarball hash:
https://sympa.inria.fr/sympa/arc/swh-devel/2016-07/msg00009.html
>> But today, we store tarball hashes, not directory hashes.
>
> We store what "guix hash" returns. ;-)
> So it is easy to migrate from tarball hashes to whatever else. :-)
True, but that other thing, as it stands, would be a nar hash (like for
‘git-fetch’), not a Git-tree hash (what SWH uses).
> I mean, it is "(sha256 (base32" and it is easy to have also
> "(sha256-tree (base32" or something like that.
Right, but that first and foremost requires daemon support.
It’s doable, but migration would have to take a long time, since this is
touching core parts of the “protocol”.
> I have not done yet the clear back-to-envelop computations. Roughly,
> there are ~23 commits on average per day updating packages, so say 70%
> of them are url-fetch, it is ~16 new tarballs per day, on average.
> How the model using a Git-repo will scale? Because, naively the
> output of "disassemble-archive" in full text (pretty-print format) for
> the hello-2.10.tar is 120KB and so 16*365*120K = ~700Mb per year
> without considering all the Git internals. Obviously, it depends on
> the number of files and I do not know if hello is a representative
> example.
Interesting, thanks for making that calculation! We could make the
format more compact if needed.
Thanks,
Ludo’.
next prev parent reply other threads:[~2020-07-21 21:23 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-02 7:29 bug#42162: gforge.inria.fr to be taken off-line in Dec. 2020 Ludovic Courtès
2020-07-02 8:50 ` zimoun
2020-07-02 10:03 ` Ludovic Courtès
2020-07-11 15:50 ` bug#42162: Recovering source tarballs Ludovic Courtès
2020-07-13 19:20 ` Christopher Baines
2020-07-20 21:27 ` zimoun
2020-07-15 16:55 ` zimoun
2020-07-20 8:39 ` Ludovic Courtès
2020-07-20 15:52 ` zimoun
2020-07-20 17:05 ` Dr. Arne Babenhauserheide
2020-07-20 19:59 ` zimoun
2020-07-21 21:22 ` Ludovic Courtès [this message]
2020-07-22 0:27 ` zimoun
2020-07-22 10:28 ` Ludovic Courtès
2020-08-03 21:10 ` Ricardo Wurmus
2020-07-30 17:36 ` Timothy Sample
2020-07-31 14:41 ` Ludovic Courtès
2020-08-03 16:59 ` Timothy Sample
2020-08-05 17:14 ` Ludovic Courtès
2020-08-05 18:57 ` Timothy Sample
2020-08-23 16:21 ` Ludovic Courtès
2020-11-03 14:26 ` Ludovic Courtès
2020-11-03 16:37 ` zimoun
2020-11-03 19:20 ` Timothy Sample
2020-11-04 16:49 ` Ludovic Courtès
2022-09-29 0:32 ` bug#42162: gforge.inria.fr to be taken off-line in Dec. 2020 Maxim Cournoyer
2022-09-29 10:56 ` zimoun
2022-09-29 15:00 ` Ludovic Courtès
2022-09-30 3:10 ` Maxim Cournoyer
2022-09-30 12:13 ` zimoun
2022-10-01 22:04 ` Ludovic Courtès
2022-10-03 15:20 ` Maxim Cournoyer
2022-10-04 21:26 ` Ludovic Courtès
2022-09-30 18:17 ` Maxime Devos
2020-08-26 10:04 ` bug#42162: Recovering source tarballs zimoun
2020-08-26 21:11 ` Timothy Sample
2020-08-27 9:41 ` zimoun
2020-08-27 12:49 ` Ludovic Courtès
2020-08-27 18:06 ` Bengt Richter
2021-01-10 19:32 ` bug#42162: gforge.inria.fr to be taken off-line in Dec. 2020 Maxim Cournoyer
2021-01-13 10:39 ` Ludovic Courtès
2021-01-13 12:27 ` Andreas Enge
2021-01-13 15:07 ` Andreas Enge
[not found] ` <handler.42162.D42162.16105343699609.notifdone@debbugs.gnu.org>
2021-01-13 14:28 ` Ludovic Courtès
2021-01-14 14:21 ` Maxim Cournoyer
2021-10-04 15:59 ` bug#42162: gforge.inria.fr is off-line Ludovic Courtès
2021-10-04 17:50 ` bug#42162: gforge.inria.fr to be taken off-line in Dec. 2020 zimoun
2021-10-07 16:07 ` Ludovic Courtès
2021-10-09 17:29 ` raingloom
2021-10-11 8:41 ` zimoun
2021-10-12 9:24 ` Ludovic Courtès
2021-10-12 10:50 ` zimoun
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: https://guix.gnu.org/
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87k0ywlg1z.fsf@gnu.org \
--to=ludo@gnu.org \
--cc=42162@debbugs.gnu.org \
--cc=Maurice.Bremond@inria.fr \
--cc=zimon.toutoune@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://git.savannah.gnu.org/cgit/guix.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).