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Alexander Monakov a4bbe8af0b xdiff: optimize xdl_hash_record_verbatim
xdl_hash_record_verbatim uses modified djb2 hash with XOR instead of ADD
for combining. The ADD-based variant is used as the basis of the modern
("GNU") symbol lookup scheme in ELF. Glibc dynamic loader received an
optimized version of this hash function thanks to Noah Goldstein [1].

Switch xdl_hash_record_verbatim to additive hashing and implement
an optimized loop following the scheme suggested by Noah.

Timing 'git log --oneline --shortstat v2.0.0..v2.5.0' under perf, I got

version | cycles, bn | instructions, bn
---------------------------------------
A         6.38         11.3
B         6.21         10.89
C         5.80          9.95
D         5.83          8.74
---------------------------------------

A: baseline (git master at e4ef0485fd)
B: plus 'xdiff: refactor xdl_hash_record()'
C: and plus this patch
D: with 'xdiff: use xxhash' by Phillip Wood

The resulting speedup for xdl_hash_record_verbatim itself is about 1.5x.

[1] https://inbox.sourceware.org/libc-alpha/20220519221803.57957-6-goldstein.w.n@gmail.com/

Signed-off-by: Alexander Monakov <amonakov@ispras.ru>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2025-08-18 08:44:49 -07:00
.github ci: use Meson's new `--slice` option 2025-07-11 09:56:34 -07:00
Documentation The fifteenth batch 2025-07-28 12:02:34 -07:00
bin-wrappers
block-sha1
builtin Merge branch 'ac/auto-comment-char-fix' 2025-07-28 12:02:34 -07:00
ci clang-format: add 'RemoveBracesLLVM' to the main config 2025-07-02 09:05:29 -07:00
compat Merge branch 'ss/compat-bswap-revamp' 2025-07-24 16:03:56 -07:00
compiler-tricks
contrib Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
ewah
git-gui Merge branch 'master' of https://github.com/j6t/git-gui 2025-07-22 13:30:52 -07:00
gitk-git Merge branch 'master' of https://github.com/j6t/gitk 2025-07-22 13:30:21 -07:00
gitweb
mergetools doc: update references to renamed AsciiDoc files 2025-06-06 15:05:47 -07:00
negotiator
oss-fuzz object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
perl contrib: better support symbolic port names in git-credential-netrc 2025-06-25 09:43:59 -07:00
po po/meson.build: add missing 'ga' language code 2025-07-16 07:34:33 -07:00
refs Merge branch 'ps/refs-files-remove-empty-parent' 2025-07-16 09:42:27 -07:00
reftable
sha1
sha1collisiondetection@855827c583
sha1dc
sha256
subprojects meson: update subproject wrappers 2025-07-11 09:56:34 -07:00
t Merge branch 'ac/auto-comment-char-fix' 2025-07-28 12:02:34 -07:00
templates
trace2
xdiff xdiff: optimize xdl_hash_record_verbatim 2025-08-18 08:44:49 -07:00
.cirrus.yml ci: update FreeBSD image to 14.3 2025-07-01 07:46:22 -07:00
.clang-format clang-format: add 'RemoveBracesLLVM' to the main config 2025-07-02 09:05:29 -07:00
.editorconfig
.gitattributes
.gitignore
.gitlab-ci.yml ci: use Meson's new `--slice` option 2025-07-11 09:56:34 -07:00
.gitmodules
.mailmap
.tsan-suppressions
CODE_OF_CONDUCT.md
COPYING
GIT-BUILD-OPTIONS.in
GIT-VERSION-FILE.in
GIT-VERSION-GEN Start 2.51 cycle, the first batch 2025-06-17 10:44:42 -07:00
INSTALL
LGPL-2.1
Makefile Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
README.md
RelNotes Start 2.51 cycle, the first batch 2025-06-17 10:44:42 -07:00
SECURITY.md
abspath.c
abspath.h
aclocal.m4
add-interactive.c
add-interactive.h
add-patch.c
advice.c
advice.h
alias.c
alias.h
alloc.c
alloc.h
apply.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
apply.h
archive-tar.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
archive-zip.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
archive.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
archive.h
attr.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
attr.h
banned.h
base85.c
base85.h
bisect.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
bisect.h
blame.c Merge branch 'ly/changed-paths-traversal' 2025-07-23 15:45:15 -07:00
blame.h
blob.c
blob.h
bloom.c bloom: replace struct bloom_key * with struct bloom_keyvec 2025-07-14 10:03:03 -07:00
bloom.h bloom: replace struct bloom_key * with struct bloom_keyvec 2025-07-14 10:03:03 -07:00
branch.c remote: remove branch->merge_name and fix branch_release() 2025-06-23 16:38:55 -07:00
branch.h
builtin.h
bulk-checkin.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
bulk-checkin.h
bundle-uri.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
bundle-uri.h
bundle.c Merge branch 'bc/use-sha256-by-default-in-3.0' 2025-07-21 09:14:25 -07:00
bundle.h
cache-tree.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
cache-tree.h
cbtree.c
cbtree.h
chdir-notify.c
chdir-notify.h
check-builtins.sh
checkout.c
checkout.h
chunk-format.c
chunk-format.h
color.c
color.h
column.c
column.h
combine-diff.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
command-list.txt
commit-graph.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
commit-graph.h object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
commit-reach.c
commit-reach.h
commit-slab-decl.h
commit-slab-impl.h
commit-slab.h
commit.c Merge branch 'rs/pop-recent-commit-with-prio-queue' 2025-07-28 12:02:34 -07:00
commit.h commit: convert pop_most_recent_commit() to prio_queue 2025-07-22 07:28:23 -07:00
common-exit.c
common-init.c
common-init.h
common-main.c
config.c Merge branch 'ac/auto-comment-char-fix' 2025-07-28 12:02:34 -07:00
config.h config: remove unneeded struct field 2025-07-15 12:21:48 -07:00
config.mak.dev
config.mak.in
config.mak.uname Merge branch 'bs/config-mak-freebsd' 2025-07-14 11:19:23 -07:00
configure.ac Merge branch 'rj/freebsd-sysinfo-build-fix' 2025-07-14 11:19:28 -07:00
connect.c Use legacy hash for legacy formats 2025-07-01 14:58:24 -07:00
connect.h
connected.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
connected.h
convert.c
convert.h
copy.c
copy.h
credential.c
credential.h
csum-file.c
csum-file.h
ctype.c
daemon.c Merge branch 'cb/daemon-reap-children' 2025-07-21 09:14:28 -07:00
date.c
date.h
decorate.c
decorate.h
delta-islands.c
delta-islands.h
delta.h
detect-compiler
diagnose.c odb: get rid of `the_repository` in `for_each()` functions 2025-07-01 14:46:36 -07:00
diagnose.h
diff-delta.c
diff-lib.c
diff-merges.c
diff-merges.h
diff-no-index.c diff-no-index: do not reference .d_type member of struct dirent 2025-06-18 13:05:29 -07:00
diff.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
diff.h
diffcore-break.c
diffcore-delta.c
diffcore-order.c
diffcore-pickaxe.c
diffcore-rename.c
diffcore-rotate.c
diffcore.h
dir-iterator.c
dir-iterator.h
dir.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
dir.h dir: move starts_with_dot(_dot)_slash to dir.h 2025-06-23 16:38:56 -07:00
editor.c
editor.h
entry.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
entry.h
environment.c repository: move 'repository_format_precious_objects' to repo scope 2025-07-07 08:31:13 -07:00
environment.h repository: move 'repository_format_precious_objects' to repo scope 2025-07-07 08:31:13 -07:00
exec-cmd.c
exec-cmd.h
fetch-negotiator.c
fetch-negotiator.h
fetch-pack.c Merge branch 'rs/pop-recent-commit-with-prio-queue' 2025-07-28 12:02:34 -07:00
fetch-pack.h
fmt-merge-msg.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
fmt-merge-msg.h
fsck.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
fsck.h
fsmonitor--daemon.h
fsmonitor-ipc.c
fsmonitor-ipc.h
fsmonitor-ll.h
fsmonitor-path-utils.h
fsmonitor-settings.c
fsmonitor-settings.h
fsmonitor.c
fsmonitor.h
generate-cmdlist.sh
generate-configlist.sh Merge branch 'jc/sed-build-fixes' 2025-06-13 13:29:14 -07:00
generate-hooklist.sh
generate-perl.sh
generate-python.sh
generate-script.sh
gettext.c
gettext.h
git-archimport.perl
git-compat-util.h Merge branch 'pw/adopt-c99-bool-officially' 2025-07-24 16:03:55 -07:00
git-curl-compat.h
git-cvsexportcommit.perl
git-cvsimport.perl
git-cvsserver.perl
git-difftool--helper.sh
git-filter-branch.sh
git-instaweb.sh
git-merge-octopus.sh
git-merge-one-file.sh
git-merge-resolve.sh
git-mergetool--lib.sh
git-mergetool.sh
git-p4.py
git-quiltimport.sh
git-request-pull.sh
git-send-email.perl Merge branch 'mc/netrc-service-names' 2025-07-14 11:19:25 -07:00
git-sh-i18n.sh
git-sh-setup.sh
git-submodule.sh
git-svn.perl
git-web--browse.sh
git-zlib.c
git-zlib.h
git.c Merge branch 'jc/you-still-use-whatchanged' 2025-06-25 14:07:35 -07:00
git.rc.in
gpg-interface.c Merge branch 'cc/fast-import-export-signature-names' 2025-07-23 15:45:16 -07:00
gpg-interface.h fast-(import|export): improve on commit signature output format 2025-07-09 16:08:29 -07:00
graph.c
graph.h
grep.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
grep.h
hash-lookup.c
hash-lookup.h
hash.c
hash.h Merge branch 'bc/use-sha256-by-default-in-3.0' 2025-07-21 09:14:25 -07:00
hashmap.c
hashmap.h
help.c Merge branch 'bc/use-sha256-by-default-in-3.0' 2025-07-21 09:14:25 -07:00
help.h
hex-ll.c
hex-ll.h
hex.c
hex.h
hook.c
hook.h
http-backend.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
http-fetch.c
http-push.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
http-walker.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
http.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
http.h
ident.c Merge branch 'sa/multi-mailmap-fix' 2025-06-24 09:48:51 -07:00
ident.h
imap-send.c Merge branch 'ag/imap-send-resurrection' 2025-07-02 12:08:05 -07:00
iterator.h
json-writer.c
json-writer.h
khash.h
kwset.c
kwset.h
levenshtein.c
levenshtein.h
line-log.c bloom: rename function operates on bloom_key 2025-07-14 10:03:02 -07:00
line-log.h
line-range.c
line-range.h
linear-assignment.c
linear-assignment.h
list-objects-filter-options.c
list-objects-filter-options.h
list-objects-filter.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
list-objects-filter.h
list-objects.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
list-objects.h
list.h
lockfile.c
lockfile.h
log-tree.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
log-tree.h
loose.c odb: get rid of `the_repository` when handling alternates 2025-07-01 14:46:36 -07:00
loose.h
ls-refs.c
ls-refs.h
mailinfo.c Merge branch 'jg/mailinfo-leakfix' 2025-06-25 14:07:37 -07:00
mailinfo.h
mailmap.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
mailmap.h
match-trees.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
match-trees.h
mem-pool.c
mem-pool.h
merge-blobs.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
merge-blobs.h
merge-ll.c
merge-ll.h
merge-ort-wrappers.c
merge-ort-wrappers.h
merge-ort.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
merge-ort.h
merge.c
merge.h
mergesort.h
meson.build Merge branch 'rj/meson-libexecdir-fix' 2025-07-24 16:03:57 -07:00
meson_options.txt
midx-write.c odb: get rid of `the_repository` in `find_odb()` 2025-07-01 14:46:35 -07:00
midx.c object-store: rename `object_directory` to `odb_source` 2025-07-01 14:46:34 -07:00
midx.h
name-hash.c
name-hash.h
notes-cache.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
notes-cache.h
notes-merge.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
notes-merge.h
notes-utils.c
notes-utils.h
notes.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
notes.h
object-file-convert.c
object-file-convert.h
object-file.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
object-file.h odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
object-name.c Merge branch 'rs/pop-recent-commit-with-prio-queue' 2025-07-28 12:02:34 -07:00
object-name.h
object.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
object.h
odb.c odb: rename `read_object_with_reference()` 2025-07-01 14:46:39 -07:00
odb.h odb: rename `read_object_with_reference()` 2025-07-01 14:46:39 -07:00
oid-array.c
oid-array.h
oidmap.c
oidmap.h
oidset.c
oidset.h
oidtree.c
oidtree.h
pack-bitmap-write.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
pack-bitmap.c Merge branch 'ly/load-bitmap-leakfix' 2025-07-15 15:18:18 -07:00
pack-bitmap.h pack-bitmap: add load corrupt bitmap test 2025-07-01 14:41:54 -07:00
pack-check.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
pack-mtimes.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
pack-mtimes.h
pack-objects.c
pack-objects.h Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
pack-revindex.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
pack-revindex.h
pack-write.c odb: get rid of `the_repository` in `odb_mkstemp()` 2025-07-01 14:46:35 -07:00
pack.h
packfile.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
packfile.h object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
pager.c
pager.h
parallel-checkout.c
parallel-checkout.h
parse-options-cb.c
parse-options.c parse-options: add precision handling for OPTION_COUNTUP 2025-07-09 08:40:32 -07:00
parse-options.h parse-options: add precision handling for OPTION_COUNTUP 2025-07-09 08:40:32 -07:00
parse.c
parse.h
patch-delta.c
patch-ids.c
patch-ids.h
path-walk.c
path-walk.h
path.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
path.h
pathspec.c
pathspec.h
pkt-line.c Use legacy hash for legacy formats 2025-07-01 14:58:24 -07:00
pkt-line.h
preload-index.c preload-index: stop depending on 'the_repository' 2025-06-10 10:10:40 -07:00
preload-index.h
pretty.c
pretty.h
prio-queue.c prio-queue: add prio_queue_replace() 2025-07-22 07:28:35 -07:00
prio-queue.h prio-queue: add prio_queue_replace() 2025-07-22 07:28:35 -07:00
progress.c
progress.h
promisor-remote.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
promisor-remote.h
prompt.c
prompt.h
protocol-caps.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
protocol-caps.h
protocol.c
protocol.h
prune-packed.c
prune-packed.h
pseudo-merge.c
pseudo-merge.h
quote.c
quote.h
range-diff.c
range-diff.h
reachable.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
reachable.h
read-cache-ll.h
read-cache.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
read-cache.h
rebase-interactive.c
rebase-interactive.h
rebase.c
rebase.h
ref-filter.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
ref-filter.h
reflog-walk.c
reflog-walk.h
reflog.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
reflog.h
refs.c Merge branch 'ph/fetch-prune-optim' 2025-07-16 09:42:27 -07:00
refs.h Merge branch 'ph/fetch-prune-optim' 2025-07-16 09:42:27 -07:00
refspec.c
refspec.h
remote-curl.c Use legacy hash for legacy formats 2025-07-01 14:58:24 -07:00
remote.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
remote.h submodule: look up remotes by URL first 2025-06-23 16:38:57 -07:00
replace-object.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
replace-object.h object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
repo-settings.c Merge branch 'ds/path-walk-2' 2025-06-17 10:44:38 -07:00
repo-settings.h Merge branch 'ds/path-walk-2' 2025-06-17 10:44:38 -07:00
repository.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
repository.h Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
rerere.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
rerere.h
reset.c
reset.h
resolve-undo.c
resolve-undo.h
revision.c Merge branch 'ly/changed-paths-traversal' 2025-07-23 15:45:15 -07:00
revision.h bloom: replace struct bloom_key * with struct bloom_keyvec 2025-07-14 10:03:03 -07:00
run-command.c
run-command.h
sane-ctype.h sane-ctype: fix compiler error on Amazon Linux 2 2025-07-10 11:18:37 -07:00
scalar.c Merge branch 'ds/path-walk-2' 2025-06-17 10:44:38 -07:00
send-pack.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
send-pack.h
sequencer.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
sequencer.h
serve.c Use legacy hash for legacy formats 2025-07-01 14:58:24 -07:00
serve.h
server-info.c object-store: rename files to "odb.{c,h}" 2025-07-01 14:46:34 -07:00
server-info.h
setup.c Merge branch 'bc/use-sha256-by-default-in-3.0' 2025-07-21 09:14:25 -07:00
setup.h setup: use the default algorithm to initialize repo format 2025-07-01 14:58:24 -07:00
sh-i18n--envsubst.c
sha1dc_git.c
sha1dc_git.h
shallow.c odb: rename `has_object()` 2025-07-01 14:46:38 -07:00
shallow.h
shared.mak
shell.c
shortlog.h
sideband.c
sideband.h
sigchain.c
sigchain.h
simple-ipc.h
sparse-index.c
sparse-index.h
split-index.c
split-index.h
stable-qsort.c
statinfo.c
statinfo.h
strbuf.c strbuf: convert predicates to return bool 2025-07-16 08:18:06 -07:00
strbuf.h strbuf: convert predicates to return bool 2025-07-16 08:18:06 -07:00
streaming.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
streaming.h
string-list.c string-list: enable sign compare warnings check 2025-07-07 08:07:46 -07:00
string-list.h
strmap.c
strmap.h
strvec.c
strvec.h
sub-process.c
sub-process.h doc: update references to renamed AsciiDoc files 2025-06-06 15:05:47 -07:00
submodule-config.c Merge branch 'ps/object-store' 2025-07-15 15:18:18 -07:00
submodule-config.h
submodule.c odb: rename `oid_object_info()` 2025-07-01 14:46:37 -07:00
submodule.h odb: get rid of `the_repository` when handling submodule sources 2025-07-01 14:46:37 -07:00
symlinks.c
symlinks.h
tag.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
tag.h
tar.h
tempfile.c
tempfile.h
thread-utils.c thread-utils.c: detect online CPU count on OpenBSD / NetBSD 2025-06-01 17:15:13 -07:00
thread-utils.h
tmp-objdir.c odb: get rid of `the_repository` when handling the primary source 2025-07-01 14:46:36 -07:00
tmp-objdir.h
trace.c
trace.h
trace2.c
trace2.h
trailer.c
trailer.h
transport-helper.c
transport-internal.h
transport.c Use legacy hash for legacy formats 2025-07-01 14:58:24 -07:00
transport.h
tree-diff.c
tree-walk.c odb: rename `read_object_with_reference()` 2025-07-01 14:46:39 -07:00
tree-walk.h
tree.c odb: rename `repo_read_object_file()` 2025-07-01 14:46:38 -07:00
tree.h
unicode-width.h
unimplemented.sh
unix-socket.c
unix-socket.h
unix-stream-server.c
unix-stream-server.h
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README.md

Build status

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