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GIT-PACK-OBJECTS(1)                              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 output.

       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

       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>-<SHA-1>.{pack,idx} files. <SHA-1> 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 .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

           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 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

           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 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

           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)) git-indexpack(1))
           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 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

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

       git-rev-list(1) git-repack(1) git-prune-packed(1)

       Part of the git(1) suite

Git 1.8.3                                        05/24/2013                              GIT-PACK-OBJECTS(1)

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