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9 commits

Author SHA1 Message Date
Jonathan Tan cbe566a071 negotiator/noop: add noop fetch negotiator
Add a noop fetch negotiator. This is introduced to allow partial clones
to skip the unneeded negotiation step when fetching missing objects
using a "git fetch" subprocess. (The implementation of spawning a "git
fetch" subprocess will be done in a subsequent patch.) But this can also
be useful for end users, e.g. as a blunt fix for object corruption.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-18 13:25:05 -07:00
Jonathan Nieder b5651a2092 experimental: default to fetch.writeCommitGraph=false
The fetch.writeCommitGraph feature makes fetches write out a commit
graph file for the newly downloaded pack on fetch.  This improves the
performance of various commands that would perform a revision walk and
eventually ought to be the default for everyone.  To prepare for that
future, it's enabled by default for users that set
feature.experimental=true to experience such future defaults.

Alas, for --unshallow fetches from a shallow clone it runs into a
snag: by the time Git has fetched the new objects and is writing a
commit graph, it has performed a revision walk and r->parsed_objects
contains information about the shallow boundary from *before* the
fetch.  The commit graph writing code is careful to avoid writing a
commit graph file in shallow repositories, but the new state is not
shallow, and the result is that from that point on, commands like "git
log" make use of a newly written commit graph file representing a
fictional history with the old shallow boundary.

We could fix this by making the commit graph writing code more careful
to avoid writing a commit graph that could have used any grafts or
shallow state, but it is possible that there are other pieces of
mutated state that fetch's commit graph writing code may be relying
on.  So disable it in the feature.experimental configuration.

Google developers have been running in this configuration (by setting
fetch.writeCommitGraph=false in the system config) to work around this
bug since it was discovered in April.  Once the fix lands, we'll
enable fetch.writeCommitGraph=true again to give it some early testing
before rolling out to a wider audience.

In other words:

- this patch only affects behavior with feature.experimental=true

- it makes feature.experimental match the configuration Google has
  been using for the last few months, meaning it would leave users in
  a better tested state than without it

- this should improve testing for other features guarded by
  feature.experimental, by making feature.experimental safer to use

Reported-by: Jay Conrod <jayconrod@google.com>
Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-07-08 16:37:43 -07:00
Damien Robert 4da9e99e6e doc: be more precise on (fetch|push).recurseSubmodules
The default value also depends on the value of submodule.recurse.
Use this opportunity to correct some grammar mistakes in
Documentation/config/fetch.txt signaled by Robert P. J. Day.

Also mention `fetch.recurseSubmodules` in fetch-options.txt. In
git-push.txt, `push.recurseSubmodules` is implicitly mentioned (by
explaining how to disable it), so no need to add it there.

Lastly add a link to `git-fetch` in `git-pull.txt` to explain the
meaning of `--recurse-submodules` there.

Signed-off-by: Damien Robert <damien.olivier.robert+git@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-04-06 13:42:43 -07:00
Junio C Hamano d96e31e390 Merge branch 'js/fetch-jobs'
"git fetch --jobs=<n>" allowed <n> parallel jobs when fetching
submodules, but this did not apply to "git fetch --multiple" that
fetches from multiple remote repositories.  It now does.

* js/fetch-jobs:
  fetch: let --jobs=<n> parallelize --multiple, too
2019-10-15 13:48:00 +09:00
Johannes Schindelin d54dea77db fetch: let --jobs=<n> parallelize --multiple, too
So far, `--jobs=<n>` only parallelizes submodule fetches/clones, not
`--multiple` fetches, which is unintuitive, given that the option's name
does not say anything about submodules in particular.

Let's change that. With this patch, also fetches from multiple remotes
are parallelized.

For backwards-compatibility (and to prepare for a use case where
submodule and multiple-remote fetches may need different parallelization
limits), the config setting `submodule.fetchJobs` still only controls
the submodule part of `git fetch`, while the newly-introduced setting
`fetch.parallel` controls both (but can be overridden for submodules
with `submodule.fetchJobs`).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-06 07:35:58 +09:00
Derrick Stolee 50f26bd035 fetch: add fetch.writeCommitGraph config setting
The commit-graph feature is now on by default, and is being
written during 'git gc' by default. Typically, Git only writes
a commit-graph when a 'git gc --auto' command passes the gc.auto
setting to actualy do work. This means that a commit-graph will
typically fall behind the commits that are being used every day.

To stay updated with the latest commits, add a step to 'git
fetch' to write a commit-graph after fetching new objects. The
fetch.writeCommitGraph config setting enables writing a split
commit-graph, so on average the cost of writing this file is
very small. Occasionally, the commit-graph chain will collapse
to a single level, and this could be slow for very large repos.

For additional use, adjust the default to be true when
feature.experimental is enabled.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-03 12:06:14 -07:00
Derrick Stolee aaf633c2ad repo-settings: create feature.experimental setting
The 'feature.experimental' setting includes config options that are
not committed to become defaults, but could use additional testing.

Update the following config settings to take new defaults, and to
use the repo_settings struct if not already using them:

* 'pack.useSparse=true'

* 'fetch.negotiationAlgorithm=skipping'

In the case of fetch.negotiationAlgorithm, the existing logic
would load the config option only when about to use the setting,
so had a die() statement on an unknown string value. This is
removed as now the config is parsed under prepare_repo_settings().
In general, this die() is probably misplaced and not valuable.
A test was removed that checked this die() statement executed.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-13 13:33:55 -07:00
Derrick Stolee cdbd70c437 fetch: add --[no-]show-forced-updates argument
After updating a set of remove refs during a 'git fetch', we walk the
commits in the new ref value and not in the old ref value to discover
if the update was a forced update. This results in two things happening
during the command:

 1. The line including the ref update has an additional "(forced-update)"
    marker at the end.

 2. The ref log for that remote branch includes a bit saying that update
    is a forced update.

For many situations, this forced-update message happens infrequently, or
is a small bit of information among many ref updates. Many users ignore
these messages, but the calculation required here slows down their fetches
significantly. Keep in mind that they do not have the opportunity to
calculate a commit-graph file containing the newly-fetched commits, so
these comparisons can be very slow.

Add a '--[no-]show-forced-updates' option that allows a user to skip this
calculation. The only permanent result is dropping the forced-update bit
in the reflog.

Include a new fetch.showForcedUpdates config setting that allows this
behavior without including the argument in every command. The config
setting is overridden by the command-line arguments.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-06-21 09:38:29 -07:00
Nguyễn Thái Ngọc Duy 561fda20b8 config.txt: move fetch-config.txt to config/
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-29 10:17:01 +09:00
Renamed from Documentation/fetch-config.txt (Browse further)