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Jeff King ab6eea6f7b receive-pack: use oidset to de-duplicate .have lines If you have an alternate object store with a very large number of refs, the peak memory usage of the sha1_array can grow high, even if most of them are duplicates that end up not being printed at all. The similar for_each_alternate_ref() code-paths in fetch-pack solve this by using flags in "struct object" to de-duplicate (and so are relying on obj_hash at the core). But we don't have a "struct object" at all in this case. We could call lookup_unknown_object() to get one, but if our goal is reducing memory footprint, it's not great: - an unknown object is as large as the largest object type (a commit), which is bigger than an oidset entry - we can free the memory after our ref advertisement, but "struct object" entries persist forever (and the receive-pack may hang around for a long time, as the bottleneck is often client upload bandwidth). So let's use an oidset. Note that unlike a sha1-array it doesn't sort the output as a side effect. However, our output is at least stable, because for_each_alternate_ref() will give us the sha1s in ref-sorted order. In one particularly pathological case with an alternate that has 60,000 unique refs out of 80 million total, this reduced the peak heap usage of "git receive-pack . </dev/null" from 13GB to 14MB. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>		2017-02-08 15:39:55 -08:00
Documentation	Git 2.12-rc0	2017-02-03 11:29:52 -08:00
block-sha1	…
builtin	receive-pack: use oidset to de-duplicate .have lines	2017-02-08 15:39:55 -08:00
ci	…
compat	Merge branch 'js/mingw-isatty' into maint	2017-01-31 13:32:11 -08:00
contrib	Merge branch 'pl/complete-diff-submodule-diff'	2017-02-03 11:25:19 -08:00
ewah	…
git-gui	git-gui 0.21.0	2016-10-20 09:33:17 -07:00
gitk-git	Merge git://ozlabs.org/~paulus/gitk	2017-01-18 10:27:59 -08:00
gitweb	Merge branch 'ab/gitweb-abbrev-links'	2016-10-26 13:14:46 -07:00
mergetools	Merge branch 'da/mergetool-xxdiff-hotkey' into maint	2017-01-17 15:11:05 -08:00
perl	Merge branch 'va/i18n-perl-scripts'	2016-12-27 00:11:40 -08:00
po	gitk: Remove translated message from comments	2017-01-18 21:12:45 +11:00
ppc	…
refs	Merge branch 'cw/log-updates-for-all-refs-really'	2017-02-03 11:25:19 -08:00
t	Merge branch 'cw/log-updates-for-all-refs-really'	2017-02-03 11:25:19 -08:00
templates	pre-receive.sample: mark it executable	2016-10-28 14:21:11 -07:00
vcs-svn	Merge branch 'mr/vcs-svn-printf-ulong' into maint	2016-09-29 16:49:37 -07:00
xdiff	Merge branch 'jc/retire-compaction-heuristics'	2017-01-10 15:24:27 -08:00
.gitattributes	…
.gitignore	relink: retire the command	2017-01-25 14:42:37 -08:00
.mailmap	Merge branch 'sg/mailmap-self'	2017-02-02 13:36:57 -08:00
.travis.yml	travis-ci: fix Perforce install on macOS	2017-01-23 10:55:00 -08:00
COPYING	…
GIT-VERSION-GEN	Git 2.12-rc0	2017-02-03 11:29:52 -08:00
INSTALL	…
LGPL-2.1	…
Makefile	add oidset API	2017-02-08 15:39:55 -08:00
README.md	README: replace gmane link with public-inbox	2016-12-15 09:30:09 -08:00
RelNotes	Almost ready for 2.11.1	2017-01-17 15:19:11 -08:00
abspath.c	Merge branch 'rs/absolute-pathdup'	2017-02-02 13:36:55 -08:00
aclocal.m4	…
advice.c	…
advice.h	…
alias.c	…
alloc.c	…
apply.c	hold_locked_index(): align error handling with hold_lockfile_for_update()	2016-12-07 11:31:59 -08:00
apply.h	…
archive-tar.c	…
archive-zip.c	archive-zip: load userdiff config	2017-01-07 18:49:30 -08:00
archive.c	archive: read local configuration	2016-11-22 13:55:20 -08:00
archive.h	archive: read local configuration	2016-11-22 13:55:20 -08:00
argv-array.c	…
argv-array.h	…
attr.c	read info/{attributes,exclude} only when in repository	2016-10-26 13:30:51 -07:00
attr.h	…
base85.c	…
bisect.c	bisect: improve English grammar of not-ancestors message	2016-12-05 14:50:38 -08:00
bisect.h	…
blob.c	…
blob.h	…
branch.c	refs: add option core.logAllRefUpdates = always	2017-01-31 10:01:24 -08:00
branch.h	create_branch: drop unused "head" parameter	2016-11-09 14:56:21 -08:00
builtin.h	difftool: add a skeleton for the upcoming builtin	2017-01-17 13:32:47 -08:00
bulk-checkin.c	compression: unify pack.compression configuration parsing	2016-11-15 21:16:22 -08:00
bulk-checkin.h	…
bundle.c	…
bundle.h	…
cache-tree.c	…
cache-tree.h	…
cache.h	Merge branch 'cw/log-updates-for-all-refs-really'	2017-02-03 11:25:19 -08:00
check-builtins.sh	…
check-racy.c	…
check_bindir	…
color.c	Merge branch 'nd/log-graph-configurable-colors'	2017-02-02 13:36:58 -08:00
color.h	…
column.c	…
column.h	…
combine-diff.c	diff_aligned_abbrev: use "struct oid"	2016-10-26 13:30:51 -07:00
command-list.txt	relink: retire the command	2017-01-25 14:42:37 -08:00
commit-slab.h	…
commit.c	commit: make ignore_non_trailer take buf/len	2016-11-29 14:22:18 -08:00
commit.h	commit: make ignore_non_trailer take buf/len	2016-11-29 14:22:18 -08:00
common-main.c	common-main: stop munging argv[0] path	2016-11-29 11:01:48 -08:00
config.c	Merge branch 'nd/config-misc-fixes' into maint	2017-01-31 13:32:06 -08:00
config.mak.in	…
config.mak.uname	xdiff: drop XDL_FAST_HASH	2016-12-06 13:27:11 -08:00
configure.ac	Merge branch 'dp/autoconf-curl-ssl' into maint	2016-10-28 09:01:13 -07:00
connect.c	Merge branch 'ls/filter-process'	2016-10-31 13:15:21 -07:00
connect.h	…
connected.c	check_connected: accept an env argument	2016-10-10 13:54:02 -07:00
connected.h	check_connected: accept an env argument	2016-10-10 13:54:02 -07:00
convert.c	Merge branch 'jc/renormalize-merge-kill-safer-crlf' into maint	2017-01-17 14:49:28 -08:00
convert.h	…
copy.c	…
credential-cache--daemon.c	i18n: credential-cache--daemon: mark advice for translation	2016-10-17 14:51:47 -07:00
credential-cache.c	…
credential-store.c	…
credential.c	…
credential.h	…
csum-file.c	…
csum-file.h	…
ctype.c	…
daemon.c	Merge branch 'jk/daemon-path-ok-check-truncation' into maint	2016-11-29 13:27:56 -08:00
date.c	…
decorate.c	…
decorate.h	…
delta.h	…
diff-delta.c	…
diff-lib.c	commit: fix empty commit creation when there's no changes but ita entries	2016-10-24 10:48:23 -07:00
diff-no-index.c	Merge branch 'jk/setup-sequence-update'	2016-09-21 15:15:24 -07:00
diff.c	use oid_to_hex_r() for converting struct object_id hashes to hex strings	2017-01-30 14:23:40 -08:00
diff.h	Merge branch 'nd/ita-empty-commit'	2016-10-27 14:58:50 -07:00
diffcore-break.c	Merge branch 'tk/diffcore-delta-remove-unused' into maint	2016-11-29 13:28:03 -08:00
diffcore-delta.c	Merge branch 'tk/diffcore-delta-remove-unused'	2016-11-17 13:45:22 -08:00
diffcore-order.c	use QSORT	2016-09-29 15:42:18 -07:00
diffcore-pickaxe.c	Merge branch 'js/regexec-buf' into maint	2016-09-29 16:49:45 -07:00
diffcore-rename.c	Merge branch 'tk/diffcore-delta-remove-unused' into maint	2016-11-29 13:28:03 -08:00
diffcore.h	Merge branch 'tk/diffcore-delta-remove-unused' into maint	2016-11-29 13:28:03 -08:00
dir-iterator.c	…
dir-iterator.h	…
dir.c	Merge branch 'bw/realpath-wo-chdir'	2017-01-18 15:12:16 -08:00
dir.h	submodule: add absorb-git-dir function	2016-12-12 15:15:07 -08:00
editor.c	…
entry.c	…
environment.c	refs: add option core.logAllRefUpdates = always	2017-01-31 10:01:24 -08:00
exec_cmd.c	Merge branch 'js/exec-path-coverity-workaround' into maint	2017-01-31 13:32:10 -08:00
exec_cmd.h	common-main: stop munging argv[0] path	2016-11-29 11:01:48 -08:00
fast-import.c	Merge branch 'mh/fast-import-notes-fix-new' into maint	2017-01-31 13:32:05 -08:00
fetch-pack.c	fetch-pack: cache results of for_each_alternate_ref	2017-02-08 15:39:55 -08:00
fetch-pack.h	…
fmt-merge-msg.h	…
fsck.c	fsck: lazily load types under --connectivity-only	2017-01-26 10:51:09 -08:00
fsck.h	…
generate-cmdlist.sh	…
gettext.c	…
gettext.h	…
git-add--interactive.perl	Merge branch 'jc/retire-compaction-heuristics'	2017-01-10 15:24:27 -08:00
git-archimport.perl	…
git-bisect.sh	…
git-compat-util.h	add QSORT_S	2017-01-23 11:02:36 -08:00
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	mergetool: honor mergetool.$tool.trustExitCode for built-in tools	2016-11-29 10:54:03 -08:00
git-mergetool.sh	mergetool: fix running in subdir when rerere enabled	2017-01-10 13:22:51 -08:00
git-p4.py	Merge branch 'gv/mingw-p4-mapuser'	2017-02-02 13:36:55 -08:00
git-parse-remote.sh	…
git-quiltimport.sh	…
git-rebase--am.sh	…
git-rebase--interactive.sh	Merge branch 'jk/rebase-i-squash-count-fix' into maint	2017-01-31 13:32:07 -08:00
git-rebase--merge.sh	…
git-rebase.sh	Merge branch 'nd/rebase-forget'	2016-12-19 14:45:35 -08:00
git-remote-testgit.sh	…
git-request-pull.sh	request-pull: drop old USAGE stuff	2017-01-15 16:23:23 -08:00
git-send-email.perl	i18n: send-email: mark composing message for translation	2016-12-14 11:00:06 -08:00
git-sh-i18n.sh	…
git-sh-setup.sh	Merge branch 'va/i18n-even-more'	2016-12-27 00:11:45 -08:00
git-stash.sh	Merge branch 'jk/stash-disable-renames-internally' into maint	2017-01-17 14:49:30 -08:00
git-submodule.sh	Merge branch 'sb/submodule-update-initial-runs-custom-script'	2017-02-03 11:25:19 -08:00
git-svn.perl	git-svn: "git worktree" awareness	2016-10-14 01:36:12 +00:00
git-web--browse.sh	…
git.c	Merge branch 'sb/unpack-trees-super-prefix'	2017-02-03 11:25:18 -08:00
git.rc	…
gpg-interface.c	gpg-interface: use more status letters	2016-10-12 10:41:59 -07:00
gpg-interface.h	gpg-interface, tag: add GPG_VERIFY_OMIT_STATUS flag	2017-01-17 16:10:22 -08:00
graph.c	Merge branch 'nd/log-graph-configurable-colors'	2017-02-02 13:36:58 -08:00
graph.h	…
grep.c	grep: add submodules as a grep source type	2016-12-22 11:47:33 -08:00
grep.h	grep: add submodules as a grep source type	2016-12-22 11:47:33 -08:00
hashmap.c	…
hashmap.h	…
help.c	help: improve is_executable() on Windows	2017-01-30 09:04:17 -08:00
help.h	…
hex.c	hex: make wraparound of the index into ring-buffer explicit	2016-10-26 10:54:11 -07:00
http-backend.c	pkt-line: rename packet_write() to packet_write_fmt()	2016-10-17 11:36:50 -07:00
http-fetch.c	…
http-push.c	…
http-walker.c	Merge branch 'jk/http-walker-limit-redirect-2.9'	2016-12-19 14:45:32 -08:00
http.c	Merge branch 'jk/http-walker-limit-redirect' into maint	2017-01-17 14:49:29 -08:00
http.h	Merge branch 'jk/http-walker-limit-redirect' into maint	2017-01-17 14:49:29 -08:00
ident.c	Merge branch 'jk/ident-ai-canonname-could-be-null' into maint	2016-10-03 13:22:32 -07:00
imap-send.c	Merge branch 'jc/cocci-xstrdup-or-null' into maint	2016-10-28 09:01:23 -07:00
iterator.h	…
khash.h	…
kwset.c	…
kwset.h	…
levenshtein.c	…
levenshtein.h	…
line-log.c	use QSORT	2016-09-29 15:42:18 -07:00
line-log.h	…
line-range.c	…
line-range.h	…
list-objects.c	…
list-objects.h	…
list.h	…
ll-merge.c	…
ll-merge.h	…
lockfile.c	lockfile: LOCK_REPORT_ON_ERROR	2016-12-07 11:31:59 -08:00
lockfile.h	lockfile: move REPORT_ON_ERROR bit elsewhere	2016-12-27 09:12:09 -08:00
log-tree.c	…
log-tree.h	…
mailinfo.c	Merge branch 'jt/mailinfo-fold-in-body-headers' into maint	2017-01-17 15:11:06 -08:00
mailinfo.h	mailinfo: handle in-body header continuations	2016-09-21 10:23:11 -07:00
mailmap.c	cocci: refactor common patterns to use xstrdup_or_null()	2016-10-12 11:22:10 -07:00
mailmap.h	…
match-trees.c	…
merge-blobs.c	…
merge-blobs.h	…
merge-recursive.c	Merge branch 'nd/qsort-in-merge-recursive' into maint	2017-01-17 15:19:03 -08:00
merge-recursive.h	…
merge.c	lockfile: LOCK_REPORT_ON_ERROR	2016-12-07 11:31:59 -08:00
mergesort.c	…
mergesort.h	…
mru.c	…
mru.h	…
name-hash.c	…
notes-cache.c	…
notes-cache.h	…
notes-merge.c	Merge branch 'va/i18n-more'	2016-09-26 16:09:18 -07:00
notes-merge.h	…
notes-utils.c	…
notes-utils.h	…
notes.c	…
notes.h	…
object.c	…
object.h	fetch-pack: cache results of for_each_alternate_ref	2017-02-08 15:39:55 -08:00
oidset.c	add oidset API	2017-02-08 15:39:55 -08:00
oidset.h	add oidset API	2017-02-08 15:39:55 -08:00
pack-bitmap-write.c	use QSORT	2016-09-29 15:42:18 -07:00
pack-bitmap.c	sha1_file: rename git_open_noatime() to git_open()	2016-10-25 10:59:13 -07:00
pack-bitmap.h	…
pack-check.c	Merge branch 'jk/verify-packfile-gently' into maint	2016-10-11 14:21:36 -07:00
pack-objects.c	…
pack-objects.h	…
pack-revindex.c	use COPY_ARRAY	2016-09-25 16:44:13 -07:00
pack-revindex.h	…
pack-write.c	use QSORT	2016-09-29 15:42:18 -07:00
pack.h	…
pager.c	Merge branch 'jk/setup-sequence-update'	2016-09-21 15:15:24 -07:00
parse-options-cb.c	Merge branch 'rs/cocci'	2016-10-17 13:25:21 -07:00
parse-options.c	parse-options: print "fatal:" before usage_msg_opt()	2016-12-14 09:58:09 -08:00
parse-options.h	Merge branch 'mh/diff-indent-heuristic'	2016-09-26 16:09:16 -07:00
patch-delta.c	…
patch-ids.c	…
patch-ids.h	…
path.c	Merge branch 'js/normalize-path-copy-ceil' into maint	2017-01-17 15:11:03 -08:00
pathspec.c	pathspec: give better message for submodule related pathspec error	2017-01-09 15:19:22 -08:00
pathspec.h	pathspec: copy and free owned memory	2017-01-08 18:04:17 -08:00
pkt-line.c	pkt-line: add functions to read/write flush terminated packet streams	2016-10-17 11:36:50 -07:00
pkt-line.h	pkt-line: add functions to read/write flush terminated packet streams	2016-10-17 11:36:50 -07:00
preload-index.c	…
pretty.c	pretty: add %(trailers) format for displaying trailers of a commit message	2016-12-11 13:58:41 -08:00
prio-queue.c	…
prio-queue.h	…
progress.c	…
progress.h	…
prompt.c	…
prompt.h	…
quote.c	…
quote.h	…
reachable.c	…
reachable.h	…
read-cache.c	Merge branch 'sb/in-core-index-doc'	2017-01-31 13:14:59 -08:00
ref-filter.c	Merge branch 'rs/qsort-s'	2017-01-31 13:15:00 -08:00
ref-filter.h	Merge branch 'st/verify-tag'	2017-01-31 13:14:58 -08:00
reflog-walk.c	…
reflog-walk.h	…
refs.c	refs: add option core.logAllRefUpdates = always	2017-01-31 10:01:24 -08:00
refs.h	refs: add option core.logAllRefUpdates = always	2017-01-31 10:01:24 -08:00
remote-curl.c	Merge branch 'dt/smart-http-detect-server-going-away' into maint	2017-01-17 15:19:03 -08:00
remote-testsvn.c	…
remote.c	Merge branch 'km/branch-get-push-while-detached' into maint	2017-01-31 13:32:08 -08:00
remote.h	remote rename: more carefully determine whether a remote is configured	2017-01-19 14:04:23 -08:00
replace_object.c	…
rerere.c	hold_locked_index(): align error handling with hold_lockfile_for_update()	2016-12-07 11:31:59 -08:00
rerere.h	…
resolve-undo.c	…
resolve-undo.h	…
revision.c	Merge branch 'vn/revision-shorthand-for-side-branch-log'	2016-10-06 14:53:10 -07:00
revision.h	…
run-command.c	Merge branch 'js/mingw-hooks-with-exe-suffix'	2017-02-02 13:36:57 -08:00
run-command.h	execv_dashed_external: wait for child on signal death	2017-01-09 13:41:40 -08:00
send-pack.c	cocci: refactor common patterns to use xstrdup_or_null()	2016-10-12 11:22:10 -07:00
send-pack.h	…
sequencer.c	sequencer (rebase -i): write out the final message	2017-01-17 14:06:01 -08:00
sequencer.h	sequencer (rebase -i): learn about the 'verbose' mode	2017-01-09 14:57:29 -08:00
server-info.c	use QSORT	2016-09-29 15:42:18 -07:00
setup.c	cache.h: expose the dying procedure for reading gitlinks	2017-01-26 11:00:58 -08:00
sh-i18n--envsubst.c	remove unnecessary check before QSORT	2016-09-29 15:42:18 -07:00
sha1-array.c	Merge branch 'rs/qsort'	2016-10-10 14:03:46 -07:00
sha1-array.h	sha1_array: let callbacks interrupt iteration	2016-09-26 11:46:41 -07:00
sha1-lookup.c	…
sha1-lookup.h	…
sha1_file.c	Merge branch 'jk/clear-delta-base-cache-fix'	2017-01-31 13:14:59 -08:00
sha1_name.c	Merge branch 'jk/no-looking-at-dotgit-outside-repo'	2016-11-01 12:58:49 -07:00
shallow.c	Merge branch 'nd/shallow-fixup' into maint	2017-01-17 15:11:05 -08:00
shell.c	…
shortlog.h	shortlog: group by committer information	2016-12-15 16:19:13 -08:00
show-index.c	…
sideband.c	…
sideband.h	…
sigchain.c	…
sigchain.h	…
split-index.c	split-index: s/eith/with/ typo fix	2016-11-01 11:48:02 -07:00
split-index.h	…
strbuf.c	link_alt_odb_entry: handle normalize_path errors	2016-10-10 13:52:36 -07:00
strbuf.h	link_alt_odb_entry: handle normalize_path errors	2016-10-10 13:52:36 -07:00
streaming.c	Merge branch 'jk/pack-objects-optim-mru'	2016-10-10 14:03:47 -07:00
streaming.h	…
string-list.c	string-list: use QSORT_S in string_list_sort()	2017-01-23 11:02:38 -08:00
string-list.h	…
submodule-config.c	Merge branch 'bw/push-submodule-only'	2017-01-31 13:14:56 -08:00
submodule-config.h	Merge branch 'bw/grep-recurse-submodules'	2017-01-18 15:12:11 -08:00
submodule.c	submodule absorbing: fix worktree/gitdir pointers recursively for non-moves	2017-01-26 11:01:04 -08:00
submodule.h	Merge branch 'bw/push-submodule-only'	2017-01-31 13:14:56 -08:00
symlinks.c	…
tag.c	gpg-interface, tag: add GPG_VERIFY_OMIT_STATUS flag	2017-01-17 16:10:22 -08:00
tag.h	…
tar.h	…
tempfile.c	…
tempfile.h	…
thread-utils.c	…
thread-utils.h	…
tmp-objdir.c	tmp-objdir: quote paths we add to alternates	2016-12-12 15:10:46 -08:00
tmp-objdir.h	tmp-objdir: introduce API for temporary object directories	2016-10-10 13:54:02 -07:00
trace.c	…
trace.h	…
trailer.c	trailer: have function to describe trailer layout	2016-11-29 14:22:18 -08:00
trailer.h	trailer: have function to describe trailer layout	2016-11-29 14:22:18 -08:00
transport-helper.c	Merge branch 'nd/shallow-deepen'	2016-10-10 14:03:50 -07:00
transport.c	for_each_alternate_ref: replace transport code with for-each-ref	2017-02-08 15:39:55 -08:00
transport.h	for_each_alternate_ref: pass name/oid instead of ref struct	2017-02-08 15:39:55 -08:00
tree-diff.c	…
tree-walk.c	grep: enable recurse-submodules to work on <tree> objects	2016-12-22 11:47:33 -08:00
tree-walk.h	fsck: handle bad trees like other errors	2016-09-27 14:09:10 -07:00
tree.c	use QSORT	2016-09-29 15:42:18 -07:00
tree.h	…
unicode_width.h	unicode_width.h: update the width tables to Unicode 9.0	2016-12-14 09:48:07 -08:00
unimplemented.sh	…
unix-socket.c	…
unix-socket.h	…
unpack-trees.c	Merge branch 'sb/unpack-trees-super-prefix'	2017-02-03 11:25:18 -08:00
unpack-trees.h	…
upload-pack.c	upload-pack: optionally allow fetching any sha1	2016-11-18 13:06:14 -08:00
url.c	…
url.h	…
urlmatch.c	…
urlmatch.h	…
usage.c	Merge branch 'jk/vreport-sanitize'	2017-01-31 13:14:56 -08:00
userdiff.c	…
userdiff.h	…
utf8.c	utf8: accept "latin-1" as ISO-8859-1	2016-09-26 18:16:23 -07:00
utf8.h	…
varint.c	…
varint.h	…
version.c	…
version.h	…
versioncmp.c	versioncmp: generalize version sort suffix reordering	2017-01-12 12:25:24 -08:00
walker.c	…
walker.h	…
wildmatch.c	…
wildmatch.h	…
worktree.c	Merge branch 'rs/absolute-pathdup'	2017-02-02 13:36:55 -08:00
worktree.h	worktree: check if a submodule uses worktrees	2016-12-12 15:15:07 -08:00
wrap-for-bin.sh	…
wrapper.c	…
write_or_die.c	run-command: move check_pipe() from write_or_die to run_command	2016-10-17 11:36:49 -07:00
ws.c	…
wt-status.c	Merge branch 'rs/object-id'	2017-02-03 11:25:19 -08:00
wt-status.h	wt-status: teach has_{unstaged,uncommitted}_changes() about submodules	2016-10-07 09:29:31 -07:00
xdiff-interface.c	Merge branch 'js/regexec-buf' into maint	2016-09-29 16:49:45 -07:00
xdiff-interface.h	…
zlib.c	…

README.md

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 http://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-.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://public-inbox.org/git, http://marc.info/?l=git and other archival sites.

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