Re: [PATCH 3/4] repack: add --sparse and pass to pack-objects

[Derrick Stolee <stolee@gmail.com>]

On 3/12/2019 9:18 AM, Nathaniel Filardo wrote:
> The sparse connectivity algorithm saves a whole lot of time when there
> are UNINTERESTING trees around.

Interesting! Do you have some performance numbers to include with
this statement?
> @@ -48,6 +49,10 @@ static int repack_config(const char *var, const char *value, void *cb)
>  		use_delta_islands = git_config_bool(var, value);
>  		return 0;
>  	}
> +	if (!strcmp(var, "pack.usesparse")) {
> +		sparse = git_config_bool(var, value);
> +		return 0;
> +	}

This part is not handled inside of `pack-objects`. Since you are not
sending '--no-sparse' when the variable 'sparse' is zero, the config
setting will automatically be picked up by the pack-objects builtin.

Now, a question of whether you _should_ allow the '--no-sparse' option
in the 'repack' command, and send it along to the inner command (when
it is present) is another question.

> @@ -366,6 +374,8 @@ int cmd_repack(int argc, const char **argv, const char *prefix)
>  	argv_array_push(&cmd.args, "--all");
>  	argv_array_push(&cmd.args, "--reflog");
>  	argv_array_push(&cmd.args, "--indexed-objects");
> +	if (sparse)
> +		argv_array_push(&cmd.args, "--sparse");
>  	if (repository_format_partial_clone)
>  		argv_array_push(&cmd.args, "--exclude-promisor-objects");
>  	if (write_bitmaps)
> 

How about a test with this new option? You can probably just add to
t5322-pack-objects-sparse.sh.

Thanks,
-Stolee