doc: fetch: document --jobs=0 behavior

[ddbeck]

CC: Jean-Noël Avila jn.avila@free.fr
cc: Patrick Steinhardt ps@pks.im

[gitgitgadget]

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[tsgabrielle]

Ok

[ddbeck]

I think the commit message needs some improvement here, but I think I'm satisfied with otherwise. If someone comes across this with the power to /allow, I'd appreciate it!

[jvns]

/allow

[gitgitgadget]

User ddbeck is now allowed to use GitGitGadget.

[ddbeck]

/preview

[gitgitgadget]

Preview email sent as pull.2047.git.1771422762553.gitgitgadget@gmail.com

[ddbeck]

/submit

[gitgitgadget]

Submitted as pull.2047.git.1771443159369.gitgitgadget@gmail.com

To fetch this version into FETCH_HEAD:

git fetch https://github.com/gitgitgadget/git/ pr-2047/ddbeck/doc-git-fetch-jobs-0-v1

To fetch this version to local tag pr-2047/ddbeck/doc-git-fetch-jobs-0-v1:

git fetch --no-tags https://github.com/gitgitgadget/git/ tag pr-2047/ddbeck/doc-git-fetch-jobs-0-v1

[gitgitgadget]

Patrick Steinhardt wrote on the Git mailing list (how to reply to this email):

On Wed, Feb 18, 2026 at 07:32:39PM +0000, Daniel D. Beck via GitGitGadget wrote:
> diff --git a/Documentation/fetch-options.adoc b/Documentation/fetch-options.adoc
> index fcba46ee9e..e15cbc51f2 100644
> --- a/Documentation/fetch-options.adoc
> +++ b/Documentation/fetch-options.adoc
> @@ -234,6 +234,8 @@ endif::git-pull[]
>  `--jobs=<n>`::
>  	Parallelize all forms of fetching up to _<n>_ jobs at a time.
>  +
> +A value of 0 will use some reasonable default.

Can't we do better though than saying "some reasonable default"? As a
user I would wonder what this is even supposed to mean. True, we don't
do so either in the documentation of "fetch.parallel". But arguably, we
should update both sites to reflect the status quo.

Going into the code we seem to fall back to `online_cpus()`. So should
we document this accordingly?

Thanks!

Patrick

[gitgitgadget]

User Patrick Steinhardt <ps@pks.im> has been added to the cc: list.

[gitgitgadget]

Junio C Hamano wrote on the Git mailing list (how to reply to this email):

"Daniel D. Beck via GitGitGadget" <gitgitgadget@gmail.com> writes:

> From: "Daniel D. Beck" <daniel@ddbeck.com>
>
> In c39952b92 (fetch: choose a sensible default with --jobs=0 again,
> 2023-02-20), the `--jobs=0` behavior was (re)introduced, but it went
> undocumented. Since this is the same behavior as `git -c fetch.parallel=0
> fetch`, which is documented, this change creates symmetry between the two
> documentation sections.

Makes sense.  In hindsight, we might have been better off if we also
called this "--jobs=auto", but documenting the behaviour is a good
first step.

Will queue.  Thanks.


>
> Signed-off-by: Daniel D. Beck <daniel@ddbeck.com>
> ---
>     doc: fetch: document --jobs=0 behavior
>
> Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-2047%2Fddbeck%2Fdoc-git-fetch-jobs-0-v1
> Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-2047/ddbeck/doc-git-fetch-jobs-0-v1
> Pull-Request: https://github.com/gitgitgadget/git/pull/2047
>
>  Documentation/fetch-options.adoc | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/Documentation/fetch-options.adoc b/Documentation/fetch-options.adoc
> index fcba46ee9e..e15cbc51f2 100644
> --- a/Documentation/fetch-options.adoc
> +++ b/Documentation/fetch-options.adoc
> @@ -234,6 +234,8 @@ endif::git-pull[]
>  `--jobs=<n>`::
>  	Parallelize all forms of fetching up to _<n>_ jobs at a time.
>  +
> +A value of 0 will use some reasonable default.
> ++
>  If the `--multiple` option was specified, the different remotes will be fetched
>  in parallel. If multiple submodules are fetched, they will be fetched in
>  parallel. To control them independently, use the config settings
>
> base-commit: 852829b3dd2fe4e7c7fc4d8badde644cf1b66c74

[gitgitgadget]

Junio C Hamano wrote on the Git mailing list (how to reply to this email):

Patrick Steinhardt <ps@pks.im> writes:

> On Wed, Feb 18, 2026 at 07:32:39PM +0000, Daniel D. Beck via GitGitGadget wrote:
>> diff --git a/Documentation/fetch-options.adoc b/Documentation/fetch-options.adoc
>> index fcba46ee9e..e15cbc51f2 100644
>> --- a/Documentation/fetch-options.adoc
>> +++ b/Documentation/fetch-options.adoc
>> @@ -234,6 +234,8 @@ endif::git-pull[]
>>  `--jobs=<n>`::
>>  	Parallelize all forms of fetching up to _<n>_ jobs at a time.
>>  +
>> +A value of 0 will use some reasonable default.
>
> Can't we do better though than saying "some reasonable default"? As a
> user I would wonder what this is even supposed to mean. True, we don't
> do so either in the documentation of "fetch.parallel". But arguably, we
> should update both sites to reflect the status quo.
>
> Going into the code we seem to fall back to `online_cpus()`. So should
> we document this accordingly?

I do not have time to dig this out myself from ancient discussion
threads, but we probably had the same discussion when "git config
--help" described the fetch.parallel with exactly the same phrasing
and decided to leave the exact implementation detail out of the
end-user facing documentation.

Thanks.

[gitgitgadget]

Patrick Steinhardt wrote on the Git mailing list (how to reply to this email):

On Thu, Feb 19, 2026 at 10:59:10AM -0800, Junio C Hamano wrote:
> Patrick Steinhardt <ps@pks.im> writes:
> 
> > On Wed, Feb 18, 2026 at 07:32:39PM +0000, Daniel D. Beck via GitGitGadget wrote:
> >> diff --git a/Documentation/fetch-options.adoc b/Documentation/fetch-options.adoc
> >> index fcba46ee9e..e15cbc51f2 100644
> >> --- a/Documentation/fetch-options.adoc
> >> +++ b/Documentation/fetch-options.adoc
> >> @@ -234,6 +234,8 @@ endif::git-pull[]
> >>  `--jobs=<n>`::
> >>  	Parallelize all forms of fetching up to _<n>_ jobs at a time.
> >>  +
> >> +A value of 0 will use some reasonable default.
> >
> > Can't we do better though than saying "some reasonable default"? As a
> > user I would wonder what this is even supposed to mean. True, we don't
> > do so either in the documentation of "fetch.parallel". But arguably, we
> > should update both sites to reflect the status quo.
> >
> > Going into the code we seem to fall back to `online_cpus()`. So should
> > we document this accordingly?
> 
> I do not have time to dig this out myself from ancient discussion
> threads, but we probably had the same discussion when "git config
> --help" described the fetch.parallel with exactly the same phrasing
> and decided to leave the exact implementation detail out of the
> end-user facing documentation.

Doesn't look like it. The thread in question is [1], and neither the
commit message nor the discussion around the patch mentioned why we
don't document what the reasonable default is.

Dscho, do you remember by chance why you decided to not be more specific
here?

Thanks!

Patrick

[1]: <pull.369.git.gitgitgadget@gmail.com>