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Abhishek Kumar 4844812b9e commit-graph: introduce commit_graph_data_slab
The struct commit is used in many contexts. However, members
`generation` and `graph_pos` are only used for commit-graph related
operations and otherwise waste memory.

This wastage would have been more pronounced as we transition to
generation number v2, which uses 64-bit generation number instead of
current 32-bits.

As they are often accessed together, let's introduce struct
commit_graph_data and move them to a commit_graph_data slab.

While the overall test suite runs just as fast as master,
(series: 26m48s, master: 27m34s, faster by 2.87%), certain commands
like `git merge-base --is-ancestor` were slowed by 40% as discovered
by Szeder Gábor [1]. After minimizing commit-slab access, the slow down
persists but is closer to 20%.

Derrick Stolee believes the slow down is attributable to the underlying
algorithm rather than the slowness of commit-slab access [2] and we will
follow-up in a later series.

[1]: https://lore.kernel.org/git/20200607195347.GA8232@szeder.dev/
[2]: https://lore.kernel.org/git/13db757a-9412-7f1e-805c-8a028c4ab2b1@gmail.com/

Signed-off-by: Abhishek Kumar <abhishekkumar8222@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-06-17 14:37:23 -07:00
.github Merge branch 'js/ci-sdk-download-fix' 2020-05-20 08:33:28 -07:00
block-sha1
builtin object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
ci Merge branch 'jk/ci-only-on-selected-branches' 2020-05-29 15:12:19 -07:00
compat Merge branch 'cb/no-more-gmtime' 2020-05-20 08:33:27 -07:00
contrib Merge branch 'vs/complete-stash-show-p-fix' 2020-06-08 18:06:29 -07:00
Documentation Merge branch 'hn/refs-cleanup' 2020-06-12 13:57:13 -07:00
ewah
git-gui Merge https://github.com/prati0100/git-gui 2020-05-21 11:15:04 -07:00
gitk-git
gitweb Merge branch 'eb/gitweb-more-trailers' 2020-05-01 13:39:56 -07:00
mergetools
negotiator
perl
po Merge branch 'master' of github.com:ruester/git-po-de 2020-05-30 11:26:53 +08:00
ppc
refs refs: improve documentation for ref iterator 2020-05-20 10:39:02 -07:00
sha1collisiondetection@855827c583
sha1dc
sha256
t object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
templates
trace2
vcs-svn
xdiff
.cirrus.yml
.clang-format
.editorconfig
.gitattributes
.gitignore Merge branch 'es/bugreport' 2020-05-01 13:39:59 -07:00
.gitmodules
.mailmap
.travis.yml
.tsan-suppressions
abspath.c
aclocal.m4
add-interactive.c
add-interactive.h
add-patch.c Merge branch 'js/checkout-p-new-file' 2020-06-08 18:06:31 -07:00
advice.c
advice.h
alias.c
alias.h
alloc.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
alloc.h object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
apply.c Use OPT_CALLBACK and OPT_CALLBACK_F 2020-04-28 10:47:10 -07:00
apply.h
archive-tar.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
archive-zip.c
archive.c
archive.h
argv-array.c
argv-array.h
attr.c
attr.h
banned.h
base85.c
bisect.c
bisect.h
blame.c blame: drop unused parameter from maybe_changed_path 2020-04-23 14:37:03 -07:00
blame.h blame: use changed-path Bloom filters 2020-04-16 15:38:06 -07:00
blob.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
blob.h
bloom.c Merge branch 'ds/line-log-on-bloom' 2020-06-08 18:06:26 -07:00
bloom.h Merge branch 'ds/line-log-on-bloom' 2020-06-08 18:06:26 -07:00
branch.c
branch.h
bugreport.c bugreport: include user interactive shell 2020-05-12 22:02:20 -07:00
builtin.h
bulk-checkin.c
bulk-checkin.h
bundle.c
bundle.h
cache-tree.c
cache-tree.h
cache.h Merge branch 'jk/oid-array-cleanups' 2020-04-22 13:42:49 -07:00
chdir-notify.c
chdir-notify.h
check-builtins.sh
check_bindir
checkout.c
checkout.h
CODE_OF_CONDUCT.md
color.c
color.h
column.c
column.h
combine-diff.c
command-list.txt Merge branch 'bc/faq' 2020-05-24 19:39:36 -07:00
commit-graph.c commit-graph: introduce commit_graph_data_slab 2020-06-17 14:37:23 -07:00
commit-graph.h commit-graph: introduce commit_graph_data_slab 2020-06-17 14:37:23 -07:00
commit-reach.c
commit-reach.h
commit-slab-decl.h commit-slab-decl.h: update include guard 2020-05-18 10:33:00 -07:00
commit-slab-impl.h
commit-slab.h
commit.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
commit.h shallow: extract a header file for shallow-related functions 2020-04-30 14:19:13 -07:00
common-main.c
config.c config: reject parsing of files over INT_MAX 2020-04-10 14:58:21 -07:00
config.h git_config_parse_key(): return baselen as size_t 2020-04-10 14:52:22 -07:00
config.mak.dev
config.mak.in
config.mak.uname Merge branch 'cb/no-more-gmtime' 2020-05-20 08:33:27 -07:00
configure.ac
connect.c stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
connect.h stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
connected.c Merge branch 'jt/connectivity-check-optim-in-partial-clone' 2020-04-22 13:42:43 -07:00
connected.h
convert.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
convert.h
copy.c
COPYING
credential-cache--daemon.c
credential-cache.c
credential-store.c Merge branch 'cb/credential-store-ignore-bogus-lines' 2020-05-08 14:25:01 -07:00
credential.c Merge branch 'js/partial-urlmatch' 2020-05-05 14:54:30 -07:00
credential.h credential: correct order of parameters for credential_match 2020-05-04 22:56:33 -07:00
csum-file.c
csum-file.h
ctype.c
daemon.c
date.c date.c: allow compact version of ISO-8601 datetime 2020-04-24 14:06:09 -07:00
decorate.c
decorate.h
delta-islands.c
delta-islands.h
delta.h
detect-compiler
diff-delta.c
diff-lib.c
diff-no-index.c
diff.c diff: add config option relative 2020-05-24 16:23:59 -07:00
diff.h
diffcore-break.c
diffcore-delta.c
diffcore-order.c
diffcore-pickaxe.c
diffcore-rename.c
diffcore.h
dir-iterator.c
dir-iterator.h
dir.c Merge branch 'en/fill-directory-exponential' 2020-04-29 16:15:31 -07:00
dir.h
editor.c
entry.c
environment.c Merge branch 'tb/shallow-cleanup' 2020-05-13 12:19:18 -07:00
exec-cmd.c
exec-cmd.h
fast-import.c Merge branch 'en/fast-import-looser-date' 2020-06-02 13:35:05 -07:00
fetch-negotiator.c
fetch-negotiator.h
fetch-pack.c stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
fetch-pack.h
fmt-merge-msg.c Merge branch 'dd/sparse-fixes' 2020-05-01 13:39:56 -07:00
fmt-merge-msg.h
fsck.c Merge branch 'rs/fsck-duplicate-names-in-trees' 2020-06-08 18:06:29 -07:00
fsck.h
fsmonitor.c
fsmonitor.h
fuzz-commit-graph.c commit-graph: close descriptors after mmap 2020-04-24 22:25:50 -07:00
fuzz-pack-headers.c
fuzz-pack-idx.c
generate-cmdlist.sh help: move list_config_help to builtin/help 2020-04-16 15:22:16 -07:00
generate-configlist.sh help: move list_config_help to builtin/help 2020-04-16 15:22:16 -07:00
gettext.c
gettext.h
git-add--interactive.perl checkout -p: handle new files correctly 2020-05-27 14:50:20 -07:00
git-archimport.perl
git-bisect.sh bisect: avoid tailing CR characters from revision in replay 2020-05-20 10:13:19 -07:00
git-compat-util.h Merge branch 'cb/no-more-gmtime' 2020-05-20 08:33:27 -07:00
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
git-mergetool.sh
git-p4.py Merge branch 'bk/p4-prepare-p4-only-fix' 2020-06-02 13:35:01 -07:00
git-parse-remote.sh
git-quiltimport.sh
git-rebase--preserve-merges.sh
git-request-pull.sh
git-send-email.perl
git-sh-i18n.sh
git-sh-setup.sh
git-submodule.sh submodule: port subcommand 'set-url' from shell to C 2020-05-08 09:17:55 -07:00
git-svn.perl
GIT-VERSION-GEN Git 2.27 2020-05-31 23:03:57 -07:00
git-web--browse.sh
git.c Merge branch 'tb/shallow-cleanup' 2020-05-13 12:19:18 -07:00
git.rc
gpg-interface.c
gpg-interface.h
graph.c graph.c: limit linkage of internal variable 2020-04-27 11:21:25 -07:00
graph.h
grep.c
grep.h
hash.h
hashmap.c
hashmap.h
help.c help: add shell-path to --build-options 2020-05-12 22:02:17 -07:00
help.h bugreport: gather git version and build info 2020-04-16 15:23:42 -07:00
hex.c
http-backend.c
http-fetch.c
http-push.c
http-walker.c
http.c http, imap-send: stop using CURLOPT_VERBOSE 2020-05-11 11:18:01 -07:00
http.h http, imap-send: stop using CURLOPT_VERBOSE 2020-05-11 11:18:01 -07:00
ident.c
imap-send.c http, imap-send: stop using CURLOPT_VERBOSE 2020-05-11 11:18:01 -07:00
INSTALL
interdiff.c
interdiff.h
iterator.h
json-writer.c
json-writer.h
khash.h
kwset.c
kwset.h
levenshtein.c
levenshtein.h
LGPL-2.1
line-log.c Merge branch 'ds/line-log-on-bloom' 2020-06-08 18:06:26 -07:00
line-log.h line-log: more responsive, incremental 'git log -L' 2020-05-11 09:33:56 -07:00
line-range.c
line-range.h
linear-assignment.c
linear-assignment.h
list-objects-filter-options.c
list-objects-filter-options.h Use OPT_CALLBACK and OPT_CALLBACK_F 2020-04-28 10:47:10 -07:00
list-objects-filter.c list-objects-filter: treat NULL filter_options as "disabled" 2020-05-04 21:57:58 -07:00
list-objects-filter.h
list-objects.c
list-objects.h
list.h
ll-merge.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
ll-merge.h
lockfile.c lockfile.c: introduce 'hold_lock_file_for_update_mode' 2020-04-27 11:27:36 -07:00
lockfile.h lockfile.c: introduce 'hold_lock_file_for_update_mode' 2020-04-27 11:27:36 -07:00
log-tree.c Merge branch 'ds/log-exclude-decoration-config' 2020-04-28 15:50:08 -07:00
log-tree.h log: add log.excludeDecoration config option 2020-04-16 11:05:48 -07:00
ls-refs.c
ls-refs.h
mailinfo.c mailinfo: disallow NUL character in mail's header 2020-04-22 14:01:03 -07:00
mailinfo.h
mailmap.c
mailmap.h
Makefile Merge branch 'lo/sparse-universal-zero-init' 2020-06-02 13:35:04 -07:00
match-trees.c
mem-pool.c
mem-pool.h
merge-blobs.c
merge-blobs.h
merge-recursive.c merge-recursive: fix rename/rename(1to2) for working tree with a binary 2020-05-14 12:14:19 -07:00
merge-recursive.h
merge.c
mergesort.c
mergesort.h
midx.c multi-pack-index: respect repack.packKeptObjects=false 2020-05-10 09:50:55 -07:00
midx.h Merge branch 'ds/multi-pack-index' 2020-05-01 13:39:55 -07:00
name-hash.c
notes-cache.c
notes-cache.h
notes-merge.c
notes-merge.h
notes-utils.c
notes-utils.h
notes.c
notes.h
object-store.h
object.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
object.h object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
oid-array.c
oid-array.h
oidmap.c
oidmap.h
oidset.c oidset: introduce 'oidset_size' 2020-04-15 09:20:29 -07:00
oidset.h Merge branch 'tb/commit-graph-split-strategy' 2020-05-01 13:39:52 -07:00
pack-bitmap-write.c
pack-bitmap.c pack-bitmap: pass object filter to fill-in traversal 2020-05-04 21:57:58 -07:00
pack-bitmap.h
pack-check.c
pack-objects.c
pack-objects.h
pack-revindex.c
pack-revindex.h
pack-write.c
pack.h
packfile.c
packfile.h
pager.c
parse-options-cb.c
parse-options.c
parse-options.h
patch-delta.c
patch-ids.c
patch-ids.h
path.c Merge branch 'dl/merge-autostash' 2020-04-29 16:15:27 -07:00
path.h
pathspec.c
pathspec.h
pkt-line.c pkt-line: define PACKET_READ_RESPONSE_END 2020-05-24 16:26:00 -07:00
pkt-line.h pkt-line: define PACKET_READ_RESPONSE_END 2020-05-24 16:26:00 -07:00
preload-index.c
pretty.c
pretty.h
prio-queue.c
prio-queue.h
progress.c progress: call trace2_region_leave() only after calling _enter() 2020-05-15 09:41:30 -07:00
progress.h progress.c: silence cgcc suggestion about internal linkage 2020-04-27 11:21:28 -07:00
promisor-remote.c Merge branch 'jt/avoid-prefetch-when-able-in-diff' 2020-04-28 15:50:04 -07:00
promisor-remote.h
prompt.c
prompt.h
protocol.c config: let feature.experimental imply protocol.version=2 2020-05-21 09:31:42 -07:00
protocol.h
prune-packed.c
prune-packed.h
quote.c
quote.h
range-diff.c range-diff: avoid negative string precision 2020-04-15 18:32:48 -07:00
range-diff.h
reachable.c
reachable.h
read-cache.c
README.md ci: retire the Azure Pipelines definition 2020-04-10 10:30:40 -07:00
rebase-interactive.c
rebase-interactive.h
rebase.c
rebase.h
ref-filter.c Merge branch 'jk/for-each-ref-multi-key-sort-fix' 2020-05-08 14:25:04 -07:00
ref-filter.h Merge branch 'jk/for-each-ref-multi-key-sort-fix' 2020-05-08 14:25:04 -07:00
reflog-walk.c
reflog-walk.h
refs.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
refs.h refs.h: clarify reflog iteration order 2020-05-20 10:39:01 -07:00
refspec.c
refspec.h
RelNotes Start the post 2.27 cycle 2020-06-02 13:35:05 -07:00
remote-curl.c stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
remote-testsvn.c
remote.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
remote.h stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
replace-object.c
replace-object.h
repo-settings.c
repository.c
repository.h Merge branch 'jc/missing-ref-store-fix' 2020-04-22 13:42:55 -07:00
rerere.c
rerere.h
reset.c Merge branch 'dl/merge-autostash' 2020-04-29 16:15:27 -07:00
reset.h
resolve-undo.c
resolve-undo.h
revision.c Merge branch 'ds/line-log-on-bloom' 2020-06-08 18:06:26 -07:00
revision.h Merge branch 'gs/commit-graph-path-filter' 2020-05-01 13:39:53 -07:00
run-command.c Merge branch 'jc/auto-gc-quiet' 2020-05-13 12:19:19 -07:00
run-command.h auto-gc: extract a reusable helper from "git fetch" 2020-05-07 12:24:33 -07:00
send-pack.c Merge branch 'tb/shallow-cleanup' 2020-05-13 12:19:18 -07:00
send-pack.h
sequencer.c Merge branch 'js/rebase-autosquash-double-fixup-fix' 2020-05-14 14:39:43 -07:00
sequencer.h Merge branch 'dl/merge-autostash' 2020-04-29 16:15:27 -07:00
serve.c pkt-line: define PACKET_READ_RESPONSE_END 2020-05-24 16:26:00 -07:00
serve.h
server-info.c
setup.c
sh-i18n--envsubst.c
sha1-file.c Merge branch 'lr/freshen-file-fix' 2020-04-28 15:49:56 -07:00
sha1-lookup.c
sha1-lookup.h
sha1-name.c Merge branch 'jc/missing-ref-store-fix' 2020-04-22 13:42:55 -07:00
sha1dc_git.c
sha1dc_git.h
shallow.c Merge branch 'tb/shallow-cleanup' 2020-05-13 12:19:18 -07:00
shallow.h shallow: use struct 'shallow_lock' for additional safety 2020-04-30 14:19:13 -07:00
shell.c
shortlog.h
sideband.c
sideband.h
sigchain.c
sigchain.h
split-index.c
split-index.h
stable-qsort.c
strbuf.c Merge branch 'bc/wildcard-credential' 2020-05-05 14:54:26 -07:00
strbuf.h Merge branch 'bc/wildcard-credential' 2020-05-05 14:54:26 -07:00
streaming.c
streaming.h
string-list.c
string-list.h
sub-process.c
sub-process.h
submodule-config.c parse_config_key(): return subsection len as size_t 2020-04-10 14:44:29 -07:00
submodule-config.h
submodule.c Merge branch 'jk/oid-array-cleanups' 2020-04-22 13:42:49 -07:00
submodule.h
symlinks.c
tag.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
tag.h
tar.h
tempfile.c tempfile.c: introduce 'create_tempfile_mode' 2020-04-27 11:27:35 -07:00
tempfile.h tempfile.c: introduce 'create_tempfile_mode' 2020-04-27 11:27:35 -07:00
thread-utils.c
thread-utils.h
tmp-objdir.c
tmp-objdir.h
trace.c http, imap-send: stop using CURLOPT_VERBOSE 2020-05-11 11:18:01 -07:00
trace.h http, imap-send: stop using CURLOPT_VERBOSE 2020-05-11 11:18:01 -07:00
trace2.c
trace2.h
trailer.c
trailer.h
transport-helper.c transport-helper: new method reject_atomic_push() 2020-04-17 12:16:32 -07:00
transport-internal.h
transport.c stateless-connect: send response end packet 2020-05-24 16:26:00 -07:00
transport.h transport-helper: new method reject_atomic_push() 2020-04-17 12:16:32 -07:00
tree-diff.c
tree-walk.c
tree-walk.h
tree.c object: drop parsed_object_pool->commit_count 2020-06-17 14:37:14 -07:00
tree.h
unicode-width.h
unimplemented.sh
unix-socket.c
unix-socket.h
unpack-trees.c Merge branch 'en/sparse-checkout' 2020-05-20 08:33:29 -07:00
unpack-trees.h Merge branch 'en/sparse-checkout' 2020-04-29 16:15:30 -07:00
upload-pack.c upload-pack: use upload_pack_data fields in receive_needs() 2020-05-18 12:58:02 -07:00
upload-pack.h
url.c
url.h
urlmatch.c credential: handle credential.<partial-URL>.<key> again 2020-04-24 15:53:46 -07:00
urlmatch.h credential: handle credential.<partial-URL>.<key> again 2020-04-24 15:53:46 -07:00
usage.c
userdiff.c Merge branch 'ah/userdiff-markdown' 2020-05-08 14:25:01 -07:00
userdiff.h
utf8.c
utf8.h
varint.c
varint.h
version.c
version.h
versioncmp.c
walker.c
walker.h
wildmatch.c
wildmatch.h
worktree.c
worktree.h
wrap-for-bin.sh
wrapper.c Merge branch 'dl/wrapper-fix-indentation' 2020-04-22 13:42:47 -07:00
write-or-die.c
ws.c
wt-status.c
wt-status.h
xdiff-interface.c
xdiff-interface.h
zlib.c

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.

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