Re: [PATCH 3/3] clean: improve performance when removing lots of directories
On Mon, Apr 6, 2015 at 7:48 AM, Erik Elfström <erik.elfstrom@gmail.com> wrote:
Show 18 quoted lines
> Before this change, clean used resolve_gitlink_ref to check for the
> presence of nested git repositories. This had the drawback of creating
> a ref_cache entry for every directory that should potentially be
> cleaned. The linear search through the ref_cache list caused a massive
> performance hit for large number of directories.
>
> Teach clean.c:remove_dirs to use setup.c:is_git_directory
> instead. is_git_directory will actually open HEAD and parse the HEAD
> ref but this implies a nested git repository and should be rare when
> cleaning.
>
> Using is_git_directory should give a more standardized check for what
> is and what isn't a git repository but also gives a slight behavioral
> change. We will now detect and respect bare and empty nested git
> repositories (only init run). Update t7300 to reflect this.
>
> The time to clean an untracked directory containing 100000 sub
> directories went from 61s to 1.7s after this change.
> Signed-off-by: Erik Elfström <erik.elfstrom@gmail.com>
> Helped-by: Jeff King <peff@peff.net>
It is customary for your sign-off to be last.
More below...
Show 17 quoted lines
> ---
> diff --git a/builtin/clean.c b/builtin/clean.c
> index 98c103f..e951bd9 100644
> --- a/builtin/clean.c
> +++ b/builtin/clean.c
> @@ -148,6 +147,24 @@ static int exclude_cb(const struct option *opt, const char *arg, int unset)
> return 0;
> }
>
> +static int is_git_repository(struct strbuf *path)
> +{
> + int ret = 0;
> + if (is_git_directory(path->buf))
> + ret = 1;
> + else {
> + int orig_path_len = path->len;
> + if (path->buf[orig_path_len - 1] != '/')Minor: I don't know how others feel about it, but I always find it a
bit disturbing to see a potential negative array access without a
safety check that orig_path_len is not 0, either directly in the
conditional or as a documenting assert().
Show 13 quoted lines
> + strbuf_addch(path, '/');
> + strbuf_addstr(path, ".git");
> + if (is_git_directory(path->buf))
> + ret = 1;
> + strbuf_setlen(path, orig_path_len);
> + }
> +
> + return ret;
> +}
> +
> static int remove_dirs(struct strbuf *path, const char *prefix, int force_flag,
> int dry_run, int quiet, int *dir_gone)
> {Eric Sunshine <sunshine@sunshineco.com>