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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. --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.
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
Git 1.9.1 11/27/2018 GIT-GC(1)