man pages section 1: User Commands

Exit Print View

Updated: July 2014

git-pack-objects (1)


git-pack-objects - Create a packed archive of objects


git pack-objects [-q | --progress | --all-progress] [--all-progress-implied]
[--no-reuse-delta] [--delta-base-offset] [--non-empty]
[--local] [--incremental] [--window=<n>] [--depth=<n>]
[--revs [--unpacked | --all]] [--stdout | base-name]
[--keep-true-parents] < object-list


Git Manual                                    GIT-PACK-OBJECTS(1)

     git-pack-objects - Create a packed archive of objects

     git pack-objects [-q | --progress | --all-progress] [--all-progress-implied]
             [--no-reuse-delta] [--delta-base-offset] [--non-empty]
             [--local] [--incremental] [--window=<n>] [--depth=<n>]
             [--revs [--unpacked | --all]] [--stdout | base-name]
             [--keep-true-parents] < object-list

     Reads list of objects from the standard input, and writes a
     packed archive with specified base-name, or to the standard

     A packed archive is an efficient way to transfer a set of
     objects between two repositories as well as an access
     efficient archival format. In a packed archive, an object is
     either stored as a compressed whole or as a difference from
     some other object. The latter is often called a delta.

     The packed archive format (.pack) is designed to be
     self-contained so that it can be unpacked without any
     further information. Therefore, each object that a delta
     depends upon must be present within the pack.

     A pack index file (.idx) is generated for fast, random
     access to the objects in the pack. Placing both the index
     file (.idx) and the packed archive (.pack) in the pack/
     subdirectory of $GIT_OBJECT_DIRECTORY (or any of the
     directories on $GIT_ALTERNATE_OBJECT_DIRECTORIES) enables
     git to read from the pack archive.

     The git unpack-objects command can read the packed archive
     and expand the objects contained in the pack into "one-file
     one-object" format; this is typically done by the smart-pull
     commands when a pack is created on-the-fly for efficient
     network transport by their peers.

         Write into a pair of files (.pack and .idx), using
         <base-name> to determine the name of the created file.
         When this option is used, the two files are written in
         <base-name>-<SHA1>.{pack,idx} files. <SHA1> is a hash of
         the sorted object names to make the resulting filename
         based on the pack content, and written to the standard
         output of the command.

         Write the pack contents (what would have been written to

Git          Last change: 02/22/2012                    1

Git Manual                                    GIT-PACK-OBJECTS(1)

         .pack file) out to the standard output.

         Read the revision arguments from the standard input,
         instead of individual object names. The revision
         arguments are processed the same way as git rev-list
         with the --objects flag uses its commit arguments to
         build the list of objects it outputs. The objects on the
         resulting list are packed.

         This implies --revs. When processing the list of
         revision arguments read from the standard input, limit
         the objects packed to those that are not already packed.

         This implies --revs. In addition to the list of revision
         arguments read from the standard input, pretend as if
         all refs under refs/ are specified to be included.

         Include unasked-for annotated tags if the object they
         reference was included in the resulting packfile. This
         can be useful to send new tags to native git clients.

     --window=<n>, --depth=<n>
         These two options affect how the objects contained in
         the pack are stored using delta compression. The objects
         are first internally sorted by type, size and optionally
         names and compared against the other objects within
         --window to see if using delta compression saves space.
         --depth limits the maximum delta depth; making it too
         deep affects the performance on the unpacker side,
         because delta data needs to be applied that many times
         to get to the necessary object. The default value for
         --window is 10 and --depth is 50.

         This option provides an additional limit on top of
         --window; the window size will dynamically scale down so
         as to not take up more than <n> bytes in memory. This is
         useful in repositories with a mix of large and small
         objects to not run out of memory with a large window,
         but still be able to take advantage of the large window
         for the smaller objects. The size can be suffixed with
         "k", "m", or "g".  --window-memory=0 makes memory usage
         unlimited, which is the default.

         Maximum size of each output pack file. The size can be
         suffixed with "k", "m", or "g". The minimum size allowed
         is limited to 1 MiB. If specified, multiple packfiles

Git          Last change: 02/22/2012                    2

Git Manual                                    GIT-PACK-OBJECTS(1)

         may be created. The default is unlimited, unless the
         config variable pack.packSizeLimit is set.

         This flag causes an object already in a local pack that
         has a .keep file to be ignored, even if it would have
         otherwise been packed.

         This flag causes an object already in a pack to be
         ignored even if it would have otherwise been packed.

         This flag causes an object that is borrowed from an
         alternate object store to be ignored even if it would
         have otherwise been packed.

         Only create a packed archive if it would contain at
         least one object.

         Progress status is reported on the standard error stream
         by default when it is attached to a terminal, unless -q
         is specified. This flag forces progress status even if
         the standard error stream is not directed to a terminal.

         When --stdout is specified then progress report is
         displayed during the object count and compression phases
         but inhibited during the write-out phase. The reason is
         that in some cases the output stream is directly linked
         to another command which may wish to display progress
         status of its own as it processes incoming pack data.
         This flag is like --progress except that it forces
         progress report for the write-out phase as well even if
         --stdout is used.

         This is used to imply --all-progress whenever progress
         display is activated. Unlike --all-progress this flag
         doesn't actually force any progress display by itself.

         This flag makes the command not to report its progress
         on the standard error stream.

         When creating a packed archive in a repository that has
         existing packs, the command reuses existing deltas. This
         sometimes results in a slightly suboptimal pack. This
         flag tells the command not to reuse existing deltas but

Git          Last change: 02/22/2012                    3

Git Manual                                    GIT-PACK-OBJECTS(1)

         compute them from scratch.

         This flag tells the command not to reuse existing object
         data at all, including non deltified object, forcing
         recompression of everything. This implies
         --no-reuse-delta. Useful only in the obscure case where
         wholesale enforcement of a different compression level
         on the packed data is desired.

         Specifies compression level for newly-compressed data in
         the generated pack. If not specified, pack compression
         level is determined first by pack.compression, then by
         core.compression, and defaults to -1, the zlib default,
         if neither is set. Add --no-reuse-object if you want to
         force a uniform compression level on all data no matter
         the source.

         Create a "thin" pack by omitting the common objects
         between a sender and a receiver in order to reduce
         network transfer. This option only makes sense in
         conjunction with --stdout.

         Note: A thin pack violates the packed archive format by
         omitting required objects and is thus unusable by git
         without making it self-contained. Use git index-pack
         --fix-thin (see git-index-pack(1)) to restore the
         self-contained property.

         A packed archive can express the base object of a delta
         as either a 20-byte object name or as an offset in the
         stream, but ancient versions of git don't understand the
         latter. By default, git pack-objects only uses the
         former format for better compatibility. This option
         allows the command to use the latter format for
         compactness. Depending on the average delta chain
         length, this option typically shrinks the resulting
         packfile by 3-5 per-cent.

         Note: Porcelain commands such as git gc (see git-gc(1)),
         git repack (see git-repack(1)) pass this option by
         default in modern git when they put objects in your
         repository into pack files. So does git bundle (see git-
         bundle(1)) when it creates a bundle.

         Specifies the number of threads to spawn when searching
         for best delta matches. This requires that pack-objects
         be compiled with pthreads otherwise this option is

Git          Last change: 02/22/2012                    4

Git Manual                                    GIT-PACK-OBJECTS(1)

         ignored with a warning. This is meant to reduce packing
         time on multiprocessor machines. The required amount of
         memory for the delta search window is however multiplied
         by the number of threads. Specifying 0 will cause git to
         auto-detect the number of CPU's and set the number of
         threads accordingly.

         This is intended to be used by the test suite only. It
         allows to force the version for the generated pack
         index, and to force 64-bit index entries on objects
         located above the given offset.

         With this option, parents that are hidden by grafts are
         packed nevertheless.

     See attributes(5) for descriptions of the following

     |Availability   | developer/versioning/git |
     |Stability      | Uncommitted              |
     git-rev-list(1) git-repack(1) git-prune-packed(1)

     Part of the git(1) suite

     This software was built from source available at  The original
     community source was downloaded from  http://git-

     Further information about this software can be found on the
     open source community website at

Git          Last change: 02/22/2012                    5