Re: [PATCH v2 5/5] fetch: Make --jobs control submodules and remotes

From: Johannes Schindelin <Johannes.Schindelin@gmx.de>
To: Palmer Dabbelt <palmer@sifive.com>
Cc: git@vger.kernel.org, peff@peff.net, e@80x24.org,
	chriscool@tuxfamily.org, gitster@pobox.com,
	jonathantanmy@google.com, tboegi@web.de, bwilliams.eng@gmail.com,
	jeffhost@microsoft.com
Subject: Re: [PATCH v2 5/5] fetch: Make --jobs control submodules and remotes
Date: Tue, 13 Aug 2019 22:16:11 +0200 (CEST)	[thread overview]
Message-ID: <nycvar.QRO.7.76.6.1908132212420.656@tvgsbejvaqbjf.bet> (raw)
In-Reply-To: <20190812213448.2649-6-palmer@sifive.com>

Hi,

On Mon, 12 Aug 2019, Palmer Dabbelt wrote:

> The existing --jobs argument was defined to control the number of jobs
> used for submodule fetching, but it makes more sense to have this
> argument control the number of jobs to be used when fetching from
> multiple remotes as well.
>
> This patch simply changes the --jobs argument parsing code to set both
> max_children_for_{submodules,fetch}, as well as noting this new behavior
> in the documentation.
>
> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
> ---

I very much miss in this description a reflection of my analysis in
https://public-inbox.org/git/nycvar.QRO.7.76.6.1907191507420.47@tvgsbejvaqbjf.bet/

Given that analysis, combined with the fact that the `--jobs` option
tries to control both the `--multiple` and `--recursive-submodules` code
paths in the end, anyway, I do doubt that it makes sense to even
introduce the `--fetch-jobs` and the `--submodule-fetch-jobs` options;
They are probably only confusing and do not add much benefit to the end
user.

Ciao,
Johannes

>  Documentation/fetch-options.txt |  4 ++++
>  builtin/fetch.c                 | 21 ++++++++++++++++++---
>  2 files changed, 22 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt
> index 5836024f1934..0915fd4ed6d5 100644
> --- a/Documentation/fetch-options.txt
> +++ b/Documentation/fetch-options.txt
> @@ -160,6 +160,10 @@ ifndef::git-pull[]
>
>  -j::
>  --jobs=<n>::
> +	Number of parallel children to be used for all forms of fetching.
> +	This is the same as passing `--submodule-fetch-jobs=<n>` and
> +	`--fetch-jobs=<n>`.
> +
>  --submodule-fetch-jobs=<n>::
>  	Number of parallel children to be used for fetching submodules.
>  	Each will fetch from different submodules, such that fetching many
> diff --git a/builtin/fetch.c b/builtin/fetch.c
> index 67d001f3f78b..41498e9efb3b 100644
> --- a/builtin/fetch.c
> +++ b/builtin/fetch.c
> @@ -114,6 +114,20 @@ static int git_fetch_config(const char *k, const char *v, void *cb)
>  	return git_default_config(k, v, cb);
>  }
>
> +static int parse_jobs_arg(const struct option *opt, const char *arg, int unset)
> +{
> +	int jobs;
> +
> +	jobs = atoi(arg);
> +	if (jobs < 1)
> +		die(_("There must be a positive number of jobs"));
> +
> +	max_children_for_submodules = jobs;
> +	max_children_for_fetch = jobs;
> +
> +	return 0;
> +}
> +
>  static int parse_refmap_arg(const struct option *opt, const char *arg, int unset)
>  {
>  	BUG_ON_OPT_NEG(unset);
> @@ -142,12 +156,13 @@ static struct option builtin_fetch_options[] = {
>  		    N_("fetch all tags and associated objects"), TAGS_SET),
>  	OPT_SET_INT('n', NULL, &tags,
>  		    N_("do not fetch all tags (--no-tags)"), TAGS_UNSET),
> -	OPT_INTEGER('j', "jobs", &max_children_for_submodules,
> +	{ OPTION_CALLBACK, 'j', "jobs", NULL, N_("jobs"),
> +		    N_("number of parallel tasks to run while fetching"),
> +		    PARSE_OPT_OPTARG, &parse_jobs_arg },
> +	OPT_INTEGER(0, "submodule-fetch-jobs", &max_children_for_submodules,
>  		    N_("number of submodules fetched in parallel")),
>  	OPT_INTEGER(0, "fetch-jobs", &max_children_for_fetch,
>  		    N_("number of remotes fetched in parallel")),
> -	OPT_INTEGER(0, "submodule-fetch-jobs", &max_children_for_submodules,
> -		    N_("number of submodules fetched in parallel")),
>  	OPT_BOOL('p', "prune", &prune,
>  		 N_("prune remote-tracking branches no longer on remote")),
>  	OPT_BOOL('P', "prune-tags", &prune_tags,
> --
> 2.21.0
>
>