add4c864b6
Enable the sparse index for the 'git blame' command. The index was already not expanded with this command, so the most interesting thing to do is to add tests that verify that 'git blame' behaves correctly when the sparse index is enabled and that its performance improves. More specifically, these cases are: 1. The index is not expanded for 'blame' when given paths in the sparse checkout cone at multiple levels. 2. Performance measurably improves for 'blame' with sparse index when given paths in the sparse checkout cone at multiple levels. The `p2000` tests demonstrate a ~60% execution time reduction when running 'blame' for a file two levels deep and and a ~30% execution time reduction for a file three levels deep. Test before after ---------------------------------------------------------------- 2000.62: git blame f2/f4/a (full-v3) 0.31 0.32 +3.2% 2000.63: git blame f2/f4/a (full-v4) 0.29 0.31 +6.9% 2000.64: git blame f2/f4/a (sparse-v3) 0.55 0.23 -58.2% 2000.65: git blame f2/f4/a (sparse-v4) 0.57 0.23 -59.6% 2000.66: git blame f2/f4/f3/a (full-v3) 0.77 0.85 +10.4% 2000.67: git blame f2/f4/f3/a (full-v4) 0.78 0.81 +3.8% 2000.68: git blame f2/f4/f3/a (sparse-v3) 1.07 0.72 -32.7% 2000.99: git blame f2/f4/f3/a (sparse-v4) 1.05 0.73 -30.5% We do not include paths outside the sparse checkout cone because blame does not support blaming files that are not present in the working directory. This is true in both sparse and full checkouts. Signed-off-by: Lessley Dennington <lessleydennington@gmail.com> Reviewed-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Git - fast, scalable, distributed revision control system
Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals.
Git is an Open Source project covered by the GNU General Public License version 2 (some parts of it are under different licenses, compatible with the GPLv2). It was originally written by Linus Torvalds with help of a group of hackers around the net.
Please read the file INSTALL for installation instructions.
Many Git online resources are accessible from https://git-scm.com/ including full documentation and Git related tools.
See Documentation/gittutorial.txt to get started, then see
Documentation/giteveryday.txt for a useful minimum set of commands, and
Documentation/git-<commandname>.txt for documentation of each command.
If git has been correctly installed, then the tutorial can also be
read with man gittutorial or git help tutorial, and the
documentation of each command with man git-<commandname> or git help <commandname>.
CVS users may also want to read Documentation/gitcvs-migration.txt
(man gitcvs-migration or git help cvs-migration if git is
installed).
The user discussion and development of Git take place on the Git mailing list -- everyone is welcome to post bug reports, feature requests, comments and patches to git@vger.kernel.org (read Documentation/SubmittingPatches for instructions on patch submission). To subscribe to the list, send an email with just "subscribe git" in the body to majordomo@vger.kernel.org. The mailing list archives are available at https://lore.kernel.org/git/, http://marc.info/?l=git and other archival sites.
Issues which are security relevant should be disclosed privately to the Git Security mailing list git-security@googlegroups.com.
The maintainer frequently sends the "What's cooking" reports that list the current status of various development topics to the mailing list. The discussion following them give a good reference for project status, development direction and remaining tasks.
The name "git" was given by Linus Torvalds when he wrote the very first version. He described the tool as "the stupid content tracker" and the name as (depending on your mood):
- random three-letter combination that is pronounceable, and not actually used by any common UNIX command. The fact that it is a mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the dictionary of slang.
- "global information tracker": you're in a good mood, and it actually works for you. Angels sing, and a light suddenly fills the room.
- "goddamn idiotic truckload of sh*t": when it breaks