# git-multi-pack-index(1) - man - phpMan

[GIT-MULTI-PACK-IN(1)](https://www.chedong.com/phpMan.php/man/GIT-MULTI-PACK-IN/1/markdown)                         Git Manual                         [GIT-MULTI-PACK-IN(1)](https://www.chedong.com/phpMan.php/man/GIT-MULTI-PACK-IN/1/markdown)



## NAME
       git-multi-pack-index - Write and verify multi-pack-indexes

## SYNOPSIS
       _git_ _multi-pack-index_ [--object-dir=<dir>] [--[no-]bitmap] <sub-command>


## DESCRIPTION
       Write or verify a multi-pack-index (MIDX) file.

## OPTIONS
       --object-dir=<dir>
           Use given directory for the location of Git objects. We check
           **<dir>/packs/multi-pack-index** for the current MIDX file, and **<dir>/packs** for the
           pack-files to index.

           **<dir>** must be an alternate of the current repository.

       --[no-]progress
           Turn progress on/off explicitly. If neither is specified, progress is shown if standard
           error is connected to a terminal. Supported by sub-commands **write**, **verify**, **expire**, and
           `repack.

       The following subcommands are available:

       write
           Write a new MIDX file. The following options are available for the **write** sub-command:

           --preferred-pack=<pack>
               Optionally specify the tie-breaking pack used when multiple packs contain the same
               object.  **<pack>** must contain at least one object. If not given, ties are broken in
               favor of the pack with the lowest mtime.

           --[no-]bitmap
               Control whether or not a multi-pack bitmap is written.

           --stdin-packs
               Write a multi-pack index containing only the set of line-delimited pack index
               basenames provided over stdin.

           --refs-snapshot=<path>
               With **--bitmap**, optionally specify a file which contains a "refs snapshot" taken prior
               to repacking.

               A reference snapshot is composed of line-delimited OIDs corresponding to the
               reference tips, usually taken by **git** **repack** prior to generating a new pack. A line
               may optionally start with a **+** character to indicate that the reference which
               corresponds to that OID is "preferred" (see [**git-config**(1)](https://www.chedong.com/phpMan.php/man/git-config/1/markdown)'s **pack.preferBitmapTips**.)

               The file given at **<path>** is expected to be readable, and can contain duplicates. (If
               a given OID is given more than once, it is marked as preferred if at least one
               instance of it begins with the special **+** marker).

       verify
           Verify the contents of the MIDX file.

       expire
           Delete the pack-files that are tracked by the MIDX file, but have no objects referenced
           by the MIDX. Rewrite the MIDX file afterward to remove all references to these
           pack-files.

       repack
           Create a new pack-file containing objects in small pack-files referenced by the
           multi-pack-index. If the size given by the **--batch-size=<size>** argument is zero, then
           create a pack containing all objects referenced by the multi-pack-index. For a non-zero
           batch size, Select the pack-files by examining packs from oldest-to-newest, computing the
           "expected size" by counting the number of objects in the pack referenced by the
           multi-pack-index, then divide by the total number of objects in the pack and multiply by
           the pack size. We select packs with expected size below the batch size until the set of
           packs have total expected size at least the batch size, or all pack-files are considered.
           If only one pack-file is selected, then do nothing. If a new pack-file is created,
           rewrite the multi-pack-index to reference the new pack-file. A later run of _git_
           _multi-pack-index_ _expire_ will delete the pack-files that were part of this batch.

           If **repack.packKeptObjects** is **false**, then any pack-files with an associated **.keep** file
           will not be selected for the batch to repack.

## EXAMPLES
       •   Write a MIDX file for the packfiles in the current **.git** directory.

               $ git multi-pack-index write


       •   Write a MIDX file for the packfiles in the current **.git** directory with a corresponding
           bitmap.

               $ git multi-pack-index write --preferred-pack=<pack> --bitmap


       •   Write a MIDX file for the packfiles in an alternate object store.

               $ git multi-pack-index --object-dir <alt> write


       •   Verify the MIDX file for the packfiles in the current **.git** directory.

               $ git multi-pack-index verify


## SEE ALSO
       See **The** **Multi-Pack-Index** **Design** **Document**[1] and **The** **Multi-Pack-Index** **Format**[2] for more
       information on the multi-pack-index feature.

## GIT
       Part of the [**git**(1)](https://www.chedong.com/phpMan.php/man/git/1/markdown) suite

## NOTES
        1. The Multi-Pack-Index Design Document
           file:///usr/share/doc/git/html/technical/multi-pack-index.html

        2. The Multi-Pack-Index Format
           file:///usr/share/doc/git/html/technical/pack-format.html



Git 2.34.1                                   02/26/2026                         [GIT-MULTI-PACK-IN(1)](https://www.chedong.com/phpMan.php/man/GIT-MULTI-PACK-IN/1/markdown)