ecf9ba20e3
The previous three changes contributed performance improvements to 'git apply', 'git add -p', and 'git reset -p' when using a sparse index. The improvement to 'git apply' also improved 'git checkout -p'. Add performance tests to demonstrate this (and to help validate that performance remains good in the future). In the truncated test output below, we see that the full checkout performance changes within noise expectations, but the sparse index cases improve 33% and then 96% for 'git add -p' and 41% and then 95% for 'git reset -p'. 'git checkout -p' improves immediatley by 91% because it does not need any change to its builtin. Test HEAD~4 HEAD~3 HEAD~2 HEAD~1 ------------------------------------------------------------------------------------- 2000.118: ... git add -p (full-v3) 0.79 0.79 +0.0% 0.82 +3.8% 0.82 +3.8% 2000.119: ... git add -p (full-v4) 0.74 0.76 +2.7% 0.74 +0.0% 0.76 +2.7% 2000.120: ... git add -p (sparse-v3) 1.94 1.28 -34.0% 0.07 -96.4% 0.07 -96.4% 2000.121: ... git add -p (sparse-v4) 1.93 1.28 -33.7% 0.06 -96.9% 0.06 -96.9% 2000.122: ... git checkout -p (full-v3) 1.18 1.18 +0.0% 1.18 +0.0% 1.19 +0.8% 2000.123: ... git checkout -p (full-v4) 1.10 1.12 +1.8% 1.11 +0.9% 1.11 +0.9% 2000.124: ... git checkout -p (sparse-v3) 1.31 0.11 -91.6% 0.11 -91.6% 0.11 -91.6% 2000.125: ... git checkout -p (sparse-v4) 1.29 0.11 -91.5% 0.11 -91.5% 0.11 -91.5% 2000.126: ... git reset -p (full-v3) 0.81 0.80 -1.2% 0.83 +2.5% 0.83 +2.5% 2000.127: ... git reset -p (full-v4) 0.78 0.77 -1.3% 0.77 -1.3% 0.78 +0.0% 2000.128: ... git reset -p (sparse-v3) 1.58 0.92 -41.8% 0.91 -42.4% 0.07 -95.6% 2000.129: ... git reset -p (sparse-v4) 1.58 0.92 -41.8% 0.92 -41.8% 0.07 -95.6% It is worth noting that if our test was more involved and had multiple hunks to evaluate, then the time spent in 'git apply' would dominate due to multiple index loads and writes. As it stands, we need the sparse index improvement in 'git add -p' itself to confirm this performance improvement. Since the change for 'git add -i' is identical, we avoid a second test case for that similar operation. Signed-off-by: Derrick Stolee <stolee@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.adoc to get started, then see
Documentation/giteveryday.adoc for a useful minimum set of commands, and
Documentation/git-<commandname>.adoc 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.adoc
(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 and Documentation/CodingGuidelines).
Those wishing to help with error message, usage and informational message
string translations (localization l10) should see po/README.md
(a po file is a Portable Object file that holds the translations).
To subscribe to the list, send an email to git+subscribe@vger.kernel.org (see https://subspace.kernel.org/subscribing.html for details). The mailing list archives are available at https://lore.kernel.org/git/, https://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