add: speed up cmd_add() by utilizing read_cache_preload()

During an "add", a call is made to run_diff_files() which calls
check_removed() for each index-entry.  The preload_index() code
distributes some of the costs across multiple threads.

Because the files checked are restricted to pathspec, adding
individual files makes no measurable impact but on a Windows repo
with ~200K files, 'git add .' drops from 6.3 seconds to 3.3 seconds
for a 47% savings.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Ben Peart 2018-11-02 09:30:50 -04:00 committed by Junio C Hamano
parent d582ea202b
commit d1664e73ad

View File

@ -445,11 +445,6 @@ int cmd_add(int argc, const char **argv, const char *prefix)
return 0;
}
if (read_cache() < 0)
die(_("index file corrupt"));
die_in_unpopulated_submodule(&the_index, prefix);
/*
* Check the "pathspec '%s' did not match any files" block
* below before enabling new magic.
@ -459,6 +454,10 @@ int cmd_add(int argc, const char **argv, const char *prefix)
PATHSPEC_SYMLINK_LEADING_PATH,
prefix, argv);
if (read_cache_preload(&pathspec) < 0)
die(_("index file corrupt"));
die_in_unpopulated_submodule(&the_index, prefix);
die_path_inside_submodule(&the_index, &pathspec);
if (add_new_files) {