git-gc(1)
NAME
git-gc - Cleanup unnecessary files and optimize the local repository
SYNOPSIS
git gc [--aggressive] [--auto] [--quiet] [--prune=<date> | --no-prune] [--force]
DESCRIPTION
Runs a number of housekeeping tasks within the current repository, such
as compressing file revisions (to reduce disk space and increase
performance) and removing unreachable objects which may have been
created from prior invocations of git add.
Users are encouraged to run this task on a regular basis within each
repository to maintain good disk space utilization and good operating
performance.
Some git commands may automatically run git gc; see the --auto flag
below for details. If you know what you're doing and all you want is to
disable this behavior permanently without further considerations, just
do:
$ git config --global gc.auto 0
OPTIONS
--aggressive
Usually git gc runs very quickly while providing good disk space
utilization and performance. This option will cause git gc to more
aggressively optimize the repository at the expense of taking much
more time. The effects of this optimization are persistent, so this
option only needs to be used occasionally; every few hundred
changesets or so.
--auto
With this option, git gc checks whether any housekeeping is
required; if not, it exits without performing any work. Some git
commands run git gc --auto after performing operations that could
create many loose objects.
Housekeeping is required if there are too many loose objects or too
many packs in the repository. If the number of loose objects
exceeds the value of the gc.auto configuration variable, then all
loose objects are combined into a single pack using git repack -d
-l. Setting the value of gc.auto to 0 disables automatic packing of
loose objects.
If the number of packs exceeds the value of gc.autoPackLimit, then
existing packs (except those marked with a .keep file) are
consolidated into a single pack by using the -A option of git
repack. Setting gc.autoPackLimit to 0 disables automatic
consolidation of packs.
--prune=<date>
Prune loose objects older than date (default is 2 weeks ago,
overridable by the config variable gc.pruneExpire). --prune=all
prunes loose objects regardless of their age (do not use
--prune=all unless you know exactly what you are doing. Unless the
repository is quiescent, you will lose newly created objects that
haven't been anchored with the refs and end up corrupting your
repository). --prune is on by default.
--no-prune
Do not prune any loose objects.
--quiet
Suppress all progress reports.
--force
Force git gc to run even if there may be another git gc instance
running on this repository.
CONFIGURATION
The optional configuration variable gc.reflogExpire can be set to
indicate how long historical entries within each branch's reflog should
remain available in this repository. The setting is expressed as a
length of time, for example 90 days or 3 months. It defaults to 90
days.
The optional configuration variable gc.reflogExpireUnreachable can be
set to indicate how long historical reflog entries which are not part
of the current branch should remain available in this repository. These
types of entries are generally created as a result of using git commit
--amend or git rebase and are the commits prior to the amend or rebase
occurring. Since these changes are not part of the current project most
users will want to expire them sooner. This option defaults to 30 days.
The above two configuration variables can be given to a pattern. For
example, this sets non-default expiry values only to remote-tracking
branches:
[gc "refs/remotes/*"]
reflogExpire = never
reflogExpireUnreachable = 3 days
The optional configuration variable gc.rerereResolved indicates how
long records of conflicted merge you resolved earlier are kept. This
defaults to 60 days.
The optional configuration variable gc.rerereUnresolved indicates how
long records of conflicted merge you have not resolved are kept. This
defaults to 15 days.
The optional configuration variable gc.packRefs determines if git gc
runs git pack-refs. This can be set to "notbare" to enable it within
all non-bare repos or it can be set to a boolean value. This defaults
to true.
The optional configuration variable 'gc.aggressiveWindow` controls how
much time is spent optimizing the delta compression of the objects in
the repository when the --aggressive option is specified. The larger
the value, the more time is spent optimizing the delta compression. See
the documentation for the --window' option in git-repack(1) for more
details. This defaults to 250.
Similarly, the optional configuration variable gc.aggressiveDepth
controls --depth option in git-repack(1). This defaults to 250.
The optional configuration variable gc.pruneExpire controls how old the
unreferenced loose objects have to be before they are pruned. The
default is "2 weeks ago".
NOTES
git gc tries very hard to be safe about the garbage it collects. In particular, it will keep not only objects referenced by your current set of branches and tags, but also objects referenced by the index, remote-tracking branches, refs saved by git filter-branch in refs/original/, or reflogs (which may reference commits in branches that were later amended or rewound). If you are expecting some objects to be collected and they aren't, check all of those locations and decide whether it makes sense in your case to remove those references.
HOOKS
The git gc --auto command will run the pre-auto-gc hook. See githooks(5) for more information.
SEE ALSO
git-prune(1) git-reflog(1) git-repack(1) git-rerere(1)
GIT
Part of the git(1) suite
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