git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: Stefan Beller <sbeller@google.com>
To: Shawn Pearce <spearce@spearce.org>
Cc: git <git@vger.kernel.org>
Subject: Re: RFC: Resumable clone based on hybrid "smart" and "dumb" HTTP
Date: Wed, 10 Feb 2016 12:23:06 -0800	[thread overview]
Message-ID: <CAGZ79kZMvxa5Np4GbShv_A6NZwVAqff94+d8MFTZwrZS+2CqeQ@mail.gmail.com> (raw)
In-Reply-To: <CAJo=hJuRxoe6tXe65ci-A35c_PWJEP7KEPFu5Ocn147HwVuo3A@mail.gmail.com>

On Wed, Feb 10, 2016 at 12:11 PM, Shawn Pearce <spearce@spearce.org> wrote:
> On Wed, Feb 10, 2016 at 10:59 AM, Shawn Pearce <spearce@spearce.org> wrote:
>>
>> ... Thoughts?
>
> Several of us at $DAY_JOB talked about this more today and thought a
> variation makes more sense:
>
> 1. Clients attempting clone ask for /info/refs?service=git-upload-pack
> like they do today.
>
> 2. Servers that support resumable clone include a "resumable"
> capability in the advertisement.

like "resumable-token=hash" similar to a push cert advertisement?

>
> 3. Updated clients on clone request GET /info/refs?service=git-resumable-clone.

Or just in the non-http case, they would terminate after the ls-remote
(including capability advertisement) was done and connect again to
a different service such as git-upload-stale-pack with the resumable
token to identify the pack.

>
> 4. The server may return a 302 Redirect to its current "mostly whole"
> pack file. This can be more flexible than "refs/heads/*", it just
> needs to be a mostly complete pack file that contains a complete graph
> from any arbitrary roots.
>
> 5. Clients fetch the file using standard HTTP GET, possibly with
> byte-ranges to resume.

In the non-http case the git-upload-stale-pack would be rsync with the
resume token to determine the file name of the pack,
such that we have resumeability.

>
> 6. Once stored and indexed with .idx, clients run `git fsck
> --lost-found` to discover the roots of the pack it downloaded. These
> are saved as temporary references.

jrn:
> I suspect we can do even faster by making index-pack do the work

    index-pack --check-self-contained-and-connected

>
> 7. Client runs incremental fetch, and then deletes the temporary
> references from 6.
>
>
> An advantage to this process is its much more flexible for the server.
> There is no additional pack-*.info file required. GC can organize
> packs anyway it wants, etc.
>
> To make step 4 really resume well, clients may need to save the first
> Location header it gets back from
> /info/refs?service=git-resumable-clone and use that on resume. Servers
> are likely to embed the pack SHA-1 in the Location header, and the
> client wants to use this on subsequent GET attempts to abort early if
> the server has deleted the pack the client is trying to obtain.
> --
> To unsubscribe from this list: send the line "unsubscribe git" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

  reply	other threads:[~2016-02-10 20:23 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-02-10 18:59 RFC: Resumable clone based on hybrid "smart" and "dumb" HTTP Shawn Pearce
2016-02-10 20:11 ` Shawn Pearce
2016-02-10 20:23   ` Stefan Beller [this message]
2016-02-10 20:57     ` Junio C Hamano
2016-02-10 21:22       ` Jonathan Nieder
2016-02-10 22:03         ` Jeff King
2016-02-10 21:01     ` Jonathan Nieder
2016-02-10 21:07       ` Junio C Hamano
2016-02-11  3:43       ` Junio C Hamano
2016-02-11 18:04         ` Shawn Pearce
2016-02-11 23:53       ` Duy Nguyen
2016-02-13  5:07         ` Junio C Hamano
2016-02-10 21:49   ` Jeff King
2016-02-10 22:17     ` Jonathan Nieder
2016-02-10 23:03       ` Jeff King
2016-02-10 22:40     ` Junio C Hamano
2016-02-11 21:32     ` Junio C Hamano
2016-02-11 21:46       ` Jeff King
2016-02-13  1:40     ` Blake Burkhart
2016-02-13 17:00       ` Jeff King
2016-02-14  2:14     ` Shawn Pearce
2016-02-14 17:05       ` Jeff King
2016-02-14 17:56         ` Shawn Pearce
2016-02-16 18:34         ` Stefan Beller

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: http://vger.kernel.org/majordomo-info.html

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAGZ79kZMvxa5Np4GbShv_A6NZwVAqff94+d8MFTZwrZS+2CqeQ@mail.gmail.com \
    --to=sbeller@google.com \
    --cc=git@vger.kernel.org \
    --cc=spearce@spearce.org \
    /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://80x24.org/mirrors/git.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).