git@vger.kernel.org mailing list mirror (one of many)
 help / color / mirror / code / Atom feed
From: Christian Couder <christian.couder@gmail.com>
To: git@vger.kernel.org
Cc: Junio C Hamano <gitster@pobox.com>, Jeff King <peff@peff.net>,
	Ben Peart <Ben.Peart@microsoft.com>,
	Jonathan Tan <jonathantanmy@google.com>,
	Jonathan Nieder <jrnieder@gmail.com>,
	Nguyen Thai Ngoc Duy <pclouds@gmail.com>,
	Mike Hommey <mh@glandium.org>,
	Lars Schneider <larsxschneider@gmail.com>,
	Eric Wong <e@80x24.org>,
	Christian Couder <chriscool@tuxfamily.org>,
	Jeff Hostetler <jeffhost@microsoft.com>,
	Eric Sunshine <sunshine@sunshineco.com>,
	Beat Bolli <dev+git@drbeat.li>
Subject: [PATCH v4 00/11] Many promisor remotes
Date: Mon,  1 Apr 2019 18:40:34 +0200	[thread overview]
Message-ID: <20190401164045.17328-1-chriscool@tuxfamily.org> (raw)

This path series is a follow up from the "remote odb" patch series
that I sent last year, which were a follow up from previous
series. See the links section for more information.

The goal of this patch series is to make it possible to have and to
fetch missing objects from multiple remotes instead of only one.

For now the fetch order is the order of the remotes in the config,
except for the remote specified by extensions.partialclone config
option which comes last in the fetch order.

I selected the name "Promisor remote" over "Partial clone remote"
because it is shorter and because it is not only about cloning.

The existing extensions.partialclone config option is respected, but
it is not written in the config when a partial clone or fetch is
made. Instead remote.<name>.promisor is set to "true". This may create
a compatibility issue, but it makes it possible to start using many
promisor remotes by just cloning and fetching from different remotes
with partial clone filters. The compatibility issue could be resolved
in a future iteration by just setting extensions.partialclone instead
of remote.<name>.promisor the first time a promisor remote is used.

The code might not work with many promisor remotes that don't all have
all the promised objects, as that would require the fetch protocol to
send packs with best effort, as described by Junio in:

https://public-inbox.org/git/xmqqpnqve71d.fsf@gitster-ct.c.googlers.com/

In general I have tried to change as few things as possible.

High level changes since the V3
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The number of patches didn't change. Their title and purpose didn't
change either.

The changes were all suggested by Junio.

everywhere:
  - changed name of promisor remote variables from "o" to "r"

patch 2/11:
  - made promisor_remote_new() static
  - changed promisor_remote_look_up() to promisor_remote_lookup()
  - changed struct promisor_remote to use a flex array
  - added check that promisor remote names doesn't start with "/"

patch 3/11:
  - implemented fetching only what is still missing
  - removed trailing blank line

4/11:
  - made "initialized" file static instead of function static
  - added purge of promisor remote list in promisor_remote_reinit()

5/11:
  - improve commit message

High level overview of this patch series
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

  - Patch 1/11:

This patch, makes functions in fetch-object.c return an error code,
which is necessary to later tell that they failed and try another
promisor remote when there is more than one. This could also just be
seen as a fix to these functions.

  - Patch 2/11:

This introduces the minimum infrastructure for promisor remotes.

  - Patch 3/11, 4/11 and 5/11:

This add a few missing bits in the promisor remote infrastructure that
will be needed in the following patches.

  - Patch 6/11:

This replaces the previous interface that used only one promisor
remote defined in extensions.partialclone with the new interface
created by the previous patches.

  - Patch 7/11:

This replaces the way a partial clone filter was handled by a new way
based on the previous patches that support more than one partial clone
filter.

  - Patch 8/11:

This patch removes the limitation in builtin/fetch.c to have only one
promisor remote.

  - Patch 9/11:

This adds test cases that shows that now more than one promisor remote
can be used and that remote.<name>.promisor is set to "true" when
fetching from a new promisor remote.

  - Patch 10/11 and 11/11:

These documentation patches explain how things can work with more than
one promisor remote.

Links
~~~~~

This patch series on GitHub:

V3: https://github.com/chriscool/git/commits/many-promisor-remotes
V3: https://github.com/chriscool/git/commits/many-promisor-remotes40
V2: https://github.com/chriscool/git/commits/many-promisor-remotes35
V1: https://github.com/chriscool/git/commits/many-promisor-remotes17

On the mailing list:

V3: https://public-inbox.org/git/20190312132959.11764-1-chriscool@tuxfamily.org/
V2: https://public-inbox.org/git/20190122144212.15119-1-chriscool@tuxfamily.org/
V1: https://public-inbox.org/git/20181211052746.16218-1-chriscool@tuxfamily.org/

This patch series is a follow up from the discussions related to
the remote odb V4 patch series:

https://public-inbox.org/git/20180802061505.2983-1-chriscool@tuxfamily.org/

Especially in:

https://public-inbox.org/git/CAP8UFD3nrhjANwNDqTwx5ZtnZNcnbAFqUN=u=LrvzuH4+3wQQA@mail.gmail.com/

I said that I would like to work on things in the following order:

  1) Teaching partial clone to attempt to fetch missing objects from
multiple remotes instead of only one using the order in the config.

  2) Simplifying the protocol for fetching missing objects so that it
can be satisfied by a lighter weight object storage system than a full
Git server.

  3) Making it possible to explicitly define an order in which the
remotes are accessed.

  4) Making the criteria for what objects can be missing more
aggressive, so that I can "git add" a large file and work with it
using Git without even having a second copy of that object in my local
object store.

And this patch series is about the 1).

The previous remote odb patch series on GitHub:

V5: https://github.com/chriscool/git/commits/remote-odb
V4: https://github.com/chriscool/git/commits/remote-odb5
V3: https://github.com/chriscool/git/commits/remote-odb3
V2: https://github.com/chriscool/git/commits/remote-odb2
V1: https://github.com/chriscool/git/commits/remote-odb1

Discussions related to previous versions of the odb patch series:

V4: https://public-inbox.org/git/20180802061505.2983-1-chriscool@tuxfamily.org/
V3: https://public-inbox.org/git/20180713174959.16748-1-chriscool@tuxfamily.org/
V2: https://public-inbox.org/git/20180630083542.20347-1-chriscool@tuxfamily.org/
V1: https://public-inbox.org/git/20180623121846.19750-1-chriscool@tuxfamily.org/


Christian Couder (11):
  fetch-object: make functions return an error code
  Add initial support for many promisor remotes
  promisor-remote: implement promisor_remote_get_direct()
  promisor-remote: add promisor_remote_reinit()
  promisor-remote: use repository_format_partial_clone
  Use promisor_remote_get_direct() and has_promisor_remote()
  promisor-remote: parse remote.*.partialclonefilter
  builtin/fetch: remove unique promisor remote limitation
  t0410: test fetching from many promisor remotes
  partial-clone: add multiple remotes in the doc
  remote: add promisor and partial clone config to the doc

 Documentation/config/remote.txt           |   8 +
 Documentation/technical/partial-clone.txt |  83 ++++++---
 Makefile                                  |   1 +
 builtin/cat-file.c                        |   5 +-
 builtin/fetch.c                           |  29 +--
 builtin/gc.c                              |   3 +-
 builtin/repack.c                          |   3 +-
 cache-tree.c                              |   3 +-
 connected.c                               |   3 +-
 fetch-object.c                            |  13 +-
 fetch-object.h                            |   4 +-
 list-objects-filter-options.c             |  51 +++---
 list-objects-filter-options.h             |   3 +-
 packfile.c                                |   3 +-
 promisor-remote.c                         | 212 ++++++++++++++++++++++
 promisor-remote.h                         |  21 +++
 sha1-file.c                               |  14 +-
 t/t0410-partial-clone.sh                  |  49 ++++-
 t/t5601-clone.sh                          |   3 +-
 t/t5616-partial-clone.sh                  |   4 +-
 unpack-trees.c                            |   6 +-
 21 files changed, 425 insertions(+), 96 deletions(-)
 create mode 100644 promisor-remote.c
 create mode 100644 promisor-remote.h

-- 
2.21.0.203.gd44fa53258


             reply	other threads:[~2019-04-01 16:41 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-01 16:40 Christian Couder [this message]
2019-04-01 16:40 ` [PATCH v4 01/11] fetch-object: make functions return an error code Christian Couder
2019-04-01 16:40 ` [PATCH v4 02/11] Add initial support for many promisor remotes Christian Couder
2019-04-03 22:08   ` SZEDER Gábor
2019-04-04  8:02     ` Christian Couder
2019-04-01 16:40 ` [PATCH v4 03/11] promisor-remote: implement promisor_remote_get_direct() Christian Couder
2019-04-01 16:40 ` [PATCH v4 04/11] promisor-remote: add promisor_remote_reinit() Christian Couder
2019-04-01 16:40 ` [PATCH v4 05/11] promisor-remote: use repository_format_partial_clone Christian Couder
2019-04-01 16:40 ` [PATCH v4 06/11] Use promisor_remote_get_direct() and has_promisor_remote() Christian Couder
2019-04-01 16:40 ` [PATCH v4 07/11] promisor-remote: parse remote.*.partialclonefilter Christian Couder
2019-04-01 16:40 ` [PATCH v4 08/11] builtin/fetch: remove unique promisor remote limitation Christian Couder
2019-04-01 16:40 ` [PATCH v4 09/11] t0410: test fetching from many promisor remotes Christian Couder
2019-04-05  0:56   ` SZEDER Gábor
2019-04-01 16:40 ` [PATCH v4 10/11] partial-clone: add multiple remotes in the doc Christian Couder
2019-04-01 16:40 ` [PATCH v4 11/11] remote: add promisor and partial clone config to " Christian Couder
2019-04-04  7:23 ` [PATCH v4 00/11] Many promisor remotes Junio C Hamano
2019-04-04  7:59   ` Christian Couder
2019-04-05 20:07   ` Johannes Schindelin

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=20190401164045.17328-1-chriscool@tuxfamily.org \
    --to=christian.couder@gmail.com \
    --cc=Ben.Peart@microsoft.com \
    --cc=chriscool@tuxfamily.org \
    --cc=dev+git@drbeat.li \
    --cc=e@80x24.org \
    --cc=git@vger.kernel.org \
    --cc=gitster@pobox.com \
    --cc=jeffhost@microsoft.com \
    --cc=jonathantanmy@google.com \
    --cc=jrnieder@gmail.com \
    --cc=larsxschneider@gmail.com \
    --cc=mh@glandium.org \
    --cc=pclouds@gmail.com \
    --cc=peff@peff.net \
    --cc=sunshine@sunshineco.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://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).