mirror of
https://github.com/git/git.git
synced 2024-11-08 02:03:12 +01:00
Mirror of https://github.com/git/git
b495697b82
When we look up a sha1 object for reading via parse_object() =>
read_sha1_file() => read_object() callpath, we first check
packfiles, and then loose objects. If we still haven't found it, we
re-scan the list of packfiles in `objects/pack`. This final step
ensures that we can co-exist with a simultaneous repack process
which creates a new pack and then prunes the old object.
This extra re-scan usually does not have a performance impact for
two reasons:
1. If an object is missing, then typically the re-scan will find a
new pack, then no more misses will occur. Or if it truly is
missing, then our next step is usually to die().
2. Re-scanning is cheap enough that we do not even notice.
However, these do not always hold. The assumption in (1) is that the
caller is expecting to find the object. This is usually the case,
but the call to `parse_object` in `everything_local` does not follow
this pattern. It is looking to see whether we have objects that the
remote side is advertising, not something we expect to
have. Therefore if we are fetching from a remote which has many refs
pointing to objects we do not have, we may end up re-scanning the
pack directory many times.
Even with this extra re-scanning, the impact is often not noticeable
due to (2); we just readdir() the packs directory and skip any packs
that are already loaded. However, if there are a large number of
packs, even enumerating the directory can be expensive, especially
if we do it repeatedly.
Having this many packs is a good sign the user should run `git gc`,
but it would still be nice to avoid having to scan the directory at
all.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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|---|---|---|
| block-sha1 | ||
| builtin | ||
| compat | ||
| contrib | ||
| Documentation | ||
| git-gui | ||
| git_remote_helpers | ||
| gitk-git | ||
| gitweb | ||
| mergetools | ||
| perl | ||
| po | ||
| ppc | ||
| t | ||
| templates | ||
| vcs-svn | ||
| xdiff | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| abspath.c | ||
| aclocal.m4 | ||
| advice.c | ||
| advice.h | ||
| alias.c | ||
| alloc.c | ||
| archive-tar.c | ||
| archive-zip.c | ||
| archive.c | ||
| archive.h | ||
| argv-array.c | ||
| argv-array.h | ||
| attr.c | ||
| attr.h | ||
| base85.c | ||
| bisect.c | ||
| bisect.h | ||
| blob.c | ||
| blob.h | ||
| branch.c | ||
| branch.h | ||
| builtin.h | ||
| bulk-checkin.c | ||
| bulk-checkin.h | ||
| bundle.c | ||
| bundle.h | ||
| cache-tree.c | ||
| cache-tree.h | ||
| cache.h | ||
| check-builtins.sh | ||
| check-racy.c | ||
| check_bindir | ||
| color.c | ||
| color.h | ||
| column.c | ||
| column.h | ||
| combine-diff.c | ||
| command-list.txt | ||
| commit.c | ||
| commit.h | ||
| config.c | ||
| config.mak.in | ||
| configure.ac | ||
| connect.c | ||
| connected.c | ||
| connected.h | ||
| convert.c | ||
| convert.h | ||
| copy.c | ||
| COPYING | ||
| credential-cache--daemon.c | ||
| credential-cache.c | ||
| credential-store.c | ||
| credential.c | ||
| credential.h | ||
| csum-file.c | ||
| csum-file.h | ||
| ctype.c | ||
| daemon.c | ||
| date.c | ||
| decorate.c | ||
| decorate.h | ||
| delta.h | ||
| diff-delta.c | ||
| diff-lib.c | ||
| diff-no-index.c | ||
| diff.c | ||
| diff.h | ||
| diffcore-break.c | ||
| diffcore-delta.c | ||
| diffcore-order.c | ||
| diffcore-pickaxe.c | ||
| diffcore-rename.c | ||
| diffcore.h | ||
| dir.c | ||
| dir.h | ||
| editor.c | ||
| entry.c | ||
| environment.c | ||
| exec_cmd.c | ||
| exec_cmd.h | ||
| fast-import.c | ||
| fetch-pack.h | ||
| fixup-builtins | ||
| fmt-merge-msg.h | ||
| fsck.c | ||
| fsck.h | ||
| generate-cmdlist.sh | ||
| gettext.c | ||
| gettext.h | ||
| git-add--interactive.perl | ||
| git-am.sh | ||
| git-archimport.perl | ||
| git-bisect.sh | ||
| git-compat-util.h | ||
| git-cvsexportcommit.perl | ||
| git-cvsimport.perl | ||
| git-cvsserver.perl | ||
| git-difftool--helper.sh | ||
| git-difftool.perl | ||
| git-filter-branch.sh | ||
| git-instaweb.sh | ||
| git-lost-found.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-parse-remote.sh | ||
| git-pull.sh | ||
| git-quiltimport.sh | ||
| git-rebase--am.sh | ||
| git-rebase--interactive.sh | ||
| git-rebase--merge.sh | ||
| git-rebase.sh | ||
| git-relink.perl | ||
| git-remote-testgit.py | ||
| git-repack.sh | ||
| git-request-pull.sh | ||
| git-send-email.perl | ||
| git-sh-i18n.sh | ||
| git-sh-setup.sh | ||
| git-stash.sh | ||
| git-submodule.sh | ||
| git-svn.perl | ||
| GIT-VERSION-GEN | ||
| git-web--browse.sh | ||
| git.c | ||
| git.spec.in | ||
| gpg-interface.c | ||
| gpg-interface.h | ||
| graph.c | ||
| graph.h | ||
| grep.c | ||
| grep.h | ||
| hash.c | ||
| hash.h | ||
| help.c | ||
| help.h | ||
| hex.c | ||
| http-backend.c | ||
| http-fetch.c | ||
| http-push.c | ||
| http-walker.c | ||
| http.c | ||
| http.h | ||
| ident.c | ||
| imap-send.c | ||
| INSTALL | ||
| kwset.c | ||
| kwset.h | ||
| levenshtein.c | ||
| levenshtein.h | ||
| LGPL-2.1 | ||
| list-objects.c | ||
| list-objects.h | ||
| ll-merge.c | ||
| ll-merge.h | ||
| lockfile.c | ||
| log-tree.c | ||
| log-tree.h | ||
| mailmap.c | ||
| mailmap.h | ||
| Makefile | ||
| match-trees.c | ||
| merge-file.c | ||
| merge-file.h | ||
| merge-recursive.c | ||
| merge-recursive.h | ||
| mergesort.c | ||
| mergesort.h | ||
| name-hash.c | ||
| notes-cache.c | ||
| notes-cache.h | ||
| notes-merge.c | ||
| notes-merge.h | ||
| notes.c | ||
| notes.h | ||
| object.c | ||
| object.h | ||
| pack-check.c | ||
| pack-refs.c | ||
| pack-refs.h | ||
| pack-revindex.c | ||
| pack-revindex.h | ||
| pack-write.c | ||
| pack.h | ||
| pager.c | ||
| parse-options-cb.c | ||
| parse-options.c | ||
| parse-options.h | ||
| patch-delta.c | ||
| patch-ids.c | ||
| patch-ids.h | ||
| path.c | ||
| pkt-line.c | ||
| pkt-line.h | ||
| preload-index.c | ||
| pretty.c | ||
| progress.c | ||
| progress.h | ||
| prompt.c | ||
| prompt.h | ||
| quote.c | ||
| quote.h | ||
| reachable.c | ||
| reachable.h | ||
| read-cache.c | ||
| README | ||
| reflog-walk.c | ||
| reflog-walk.h | ||
| refs.c | ||
| refs.h | ||
| RelNotes | ||
| remote-curl.c | ||
| remote.c | ||
| remote.h | ||
| replace_object.c | ||
| rerere.c | ||
| rerere.h | ||
| resolve-undo.c | ||
| resolve-undo.h | ||
| revision.c | ||
| revision.h | ||
| run-command.c | ||
| run-command.h | ||
| send-pack.h | ||
| sequencer.c | ||
| sequencer.h | ||
| server-info.c | ||
| setup.c | ||
| sh-i18n--envsubst.c | ||
| sha1-array.c | ||
| sha1-array.h | ||
| sha1-lookup.c | ||
| sha1-lookup.h | ||
| sha1_file.c | ||
| sha1_name.c | ||
| shallow.c | ||
| shell.c | ||
| shortlog.h | ||
| show-index.c | ||
| sideband.c | ||
| sideband.h | ||
| sigchain.c | ||
| sigchain.h | ||
| strbuf.c | ||
| strbuf.h | ||
| streaming.c | ||
| streaming.h | ||
| string-list.c | ||
| string-list.h | ||
| submodule.c | ||
| submodule.h | ||
| symlinks.c | ||
| tag.c | ||
| tag.h | ||
| tar.h | ||
| test-chmtime.c | ||
| test-ctype.c | ||
| test-date.c | ||
| test-delta.c | ||
| test-dump-cache-tree.c | ||
| test-genrandom.c | ||
| test-index-version.c | ||
| test-line-buffer.c | ||
| test-match-trees.c | ||
| test-mergesort.c | ||
| test-mktemp.c | ||
| test-parse-options.c | ||
| test-path-utils.c | ||
| test-regex.c | ||
| test-revision-walking.c | ||
| test-run-command.c | ||
| test-scrap-cache-tree.c | ||
| test-sha1.c | ||
| test-sha1.sh | ||
| test-sigchain.c | ||
| test-subprocess.c | ||
| test-svn-fe.c | ||
| thread-utils.c | ||
| thread-utils.h | ||
| trace.c | ||
| transport-helper.c | ||
| transport.c | ||
| transport.h | ||
| tree-diff.c | ||
| tree-walk.c | ||
| tree-walk.h | ||
| tree.c | ||
| tree.h | ||
| unimplemented.sh | ||
| unix-socket.c | ||
| unix-socket.h | ||
| unpack-trees.c | ||
| unpack-trees.h | ||
| upload-pack.c | ||
| url.c | ||
| url.h | ||
| usage.c | ||
| userdiff.c | ||
| userdiff.h | ||
| utf8.c | ||
| utf8.h | ||
| varint.c | ||
| varint.h | ||
| version.c | ||
| version.h | ||
| walker.c | ||
| walker.h | ||
| wrap-for-bin.sh | ||
| wrapper.c | ||
| write_or_die.c | ||
| ws.c | ||
| wt-status.c | ||
| wt-status.h | ||
| xdiff-interface.c | ||
| xdiff-interface.h | ||
| zlib.c | ||
////////////////////////////////////////////////////////////////
GIT - the stupid content tracker
////////////////////////////////////////////////////////////////
"git" can mean anything, 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
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.
It was originally written by Linus Torvalds with help of a group of
hackers around the net. It is currently maintained by Junio C Hamano.
Please read the file INSTALL for installation instructions.
See Documentation/gittutorial.txt to get started, then see
Documentation/everyday.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).
Many Git online resources are accessible from http://git-scm.com/
including full documentation and Git related tools.
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 http://marc.theaimsgroup.com/?l=git and other archival
sites.
The messages titled "A note from the maintainer", "What's in
git.git (stable)" and "What's cooking in git.git (topics)" and
the discussion following them on the mailing list give a good
reference for project status, development direction and
remaining tasks.