mirror of
https://github.com/git/git.git
synced 2024-05-26 16:26:14 +02:00
9218c6a40c
When multiple packs in the multi-pack index contain the same object, the MIDX machinery must make a choice about which pack it associates with that object. Prior to this patch, the lowest-ordered[1] pack was always selected. Pack selection for duplicate objects is relatively unimportant today, but it will become important for multi-pack bitmaps. This is because we can only invoke the pack-reuse mechanism when all of the bits for reused objects come from the reuse pack (in order to ensure that all reused deltas can find their base objects in the same pack). To encourage the pack selection process to prefer one pack over another (the pack to be preferred is the one a caller would like to later use as a reuse pack), introduce the concept of a "preferred pack". When provided, the MIDX code will always prefer an object found in a preferred pack over any other. No format changes are required to store the preferred pack, since it will be able to be inferred with a corresponding MIDX bitmap, by looking up the pack associated with the object in the first bit position (this ordering is described in detail in a subsequent commit). [1]: the ordering is specified by MIDX internals; for our purposes we can consider the "lowest ordered" pack to be "the one with the most-recent mtime. Signed-off-by: Taylor Blau <me@ttaylorr.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
107 lines
3.2 KiB
Plaintext
107 lines
3.2 KiB
Plaintext
git-multi-pack-index(1)
|
|
=======================
|
|
|
|
NAME
|
|
----
|
|
git-multi-pack-index - Write and verify multi-pack-indexes
|
|
|
|
|
|
SYNOPSIS
|
|
--------
|
|
[verse]
|
|
'git multi-pack-index' [--object-dir=<dir>] [--[no-]progress]
|
|
[--preferred-pack=<pack>] <subcommand>
|
|
|
|
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.
|
|
|
|
--[no-]progress::
|
|
Turn progress on/off explicitly. If neither is specified, progress is
|
|
shown if standard error is connected to a terminal.
|
|
|
|
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. If not given,
|
|
ties are broken in favor of the pack with the lowest
|
|
mtime.
|
|
--
|
|
|
|
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 folder.
|
|
+
|
|
-----------------------------------------------
|
|
$ git multi-pack-index write
|
|
-----------------------------------------------
|
|
|
|
* 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 folder.
|
|
+
|
|
-----------------------------------------------
|
|
$ git multi-pack-index verify
|
|
-----------------------------------------------
|
|
|
|
|
|
SEE ALSO
|
|
--------
|
|
See link:technical/multi-pack-index.html[The Multi-Pack-Index Design
|
|
Document] and link:technical/pack-format.html[The Multi-Pack-Index
|
|
Format] for more information on the multi-pack-index feature.
|
|
|
|
|
|
GIT
|
|
---
|
|
Part of the linkgit:git[1] suite
|