Commit Graph

19 Commits

Author SHA1 Message Date
Junio C Hamano
249d54b231 Merge branch 'jk/repack-pack-keep-objects'
* jk/repack-pack-keep-objects:
  repack: add `repack.packKeptObjects` config var
2014-03-18 13:50:29 -07:00
Jeff King
ee34a2bead repack: add repack.packKeptObjects config var
The git-repack command always passes `--honor-pack-keep`
to pack-objects. This has traditionally been a good thing,
as we do not want to duplicate those objects in a new pack,
and we are not going to delete the old pack.

However, when bitmaps are in use, it is important for a full
repack to include all reachable objects, even if they may be
duplicated in a .keep pack. Otherwise, we cannot generate
the bitmaps, as the on-disk format requires the set of
objects in the pack to be fully closed.

Even if the repository does not generally have .keep files,
a simultaneous push could cause a race condition in which a
.keep file exists at the moment of a repack. The repack may
try to include those objects in one of two situations:

  1. The pushed .keep pack contains objects that were
     already in the repository (e.g., blobs due to a revert of
     an old commit).

  2. Receive-pack updates the refs, making the objects
     reachable, but before it removes the .keep file, the
     repack runs.

In either case, we may prefer to duplicate some objects in
the new, full pack, and let the next repack (after the .keep
file is cleaned up) take care of removing them.

This patch introduces both a command-line and config option
to disable the `--honor-pack-keep` option.  By default, it
is triggered when pack.writeBitmaps (or `--write-bitmap-index`
is turned on), but specifying it explicitly can override the
behavior (e.g., in cases where you prefer .keep files to
bitmaps, but only when they are present).

Note that this option just disables the pack-objects
behavior. We still leave packs with a .keep in place, as we
do not necessarily know that we have duplicated all of their
objects.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-03 12:21:49 -08:00
Junio C Hamano
0f9e62e084 Merge branch 'jk/pack-bitmap'
Borrow the bitmap index into packfiles from JGit to speed up
enumeration of objects involved in a commit range without having to
fully traverse the history.

* jk/pack-bitmap: (26 commits)
  ewah: unconditionally ntohll ewah data
  ewah: support platforms that require aligned reads
  read-cache: use get_be32 instead of hand-rolled ntoh_l
  block-sha1: factor out get_be and put_be wrappers
  do not discard revindex when re-preparing packfiles
  pack-bitmap: implement optional name_hash cache
  t/perf: add tests for pack bitmaps
  t: add basic bitmap functionality tests
  count-objects: recognize .bitmap in garbage-checking
  repack: consider bitmaps when performing repacks
  repack: handle optional files created by pack-objects
  repack: turn exts array into array-of-struct
  repack: stop using magic number for ARRAY_SIZE(exts)
  pack-objects: implement bitmap writing
  rev-list: add bitmap mode to speed up object lists
  pack-objects: use bitmaps when packing objects
  pack-objects: split add_object_entry
  pack-bitmap: add support for bitmap indexes
  documentation: add documentation for the bitmap format
  ewah: compressed bitmap implementation
  ...
2014-02-27 14:01:48 -08:00
Junio C Hamano
2171c0c36f Merge branch 'tb/repack-fix-renames' (early part)
Finishing touches to the "rewrite repack in C" series.

* 'tb/repack-fix-renames' (early part):
  repack.c: rename and unlink pack file if it exists
2014-02-05 12:02:29 -08:00
Torsten Bögershausen
9d7fbfd204 repack.c: rename and unlink pack file if it exists
When a repo was fully repacked, and is repacked again, we may run
into the situation that "new" packfiles have the same name as
already existing ones (traditionally packfiles have been named after
the list of names of objects in them, so repacking all the objects
in a single pack would have produced a packfile with the same name).

The logic is to rename the existing ones into filename like
"old-XXX", create the new ones and then remove the "old-" ones.
When something went wrong in the middle, this sequence is rolled
back by renaming the "old-" files back.

The renaming into "old-" did not work as intended, because
file_exists() was done on "XXX", not "pack-XXX".  Also when rolling
back the change, the code tried to rename "old-pack-XXX" but the
saved ones are named "old-XXX", so this couldn't have worked.

Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-05 11:58:49 -08:00
Junio C Hamano
4110639865 Merge branch 'sb/repack-in-c'
"git repack --max-pack-size=8g" stopped being parsed correctly when
the command was reimplemented in C.

* sb/repack-in-c:
  repack: propagate pack-objects options as strings
  repack: make parsed string options const-correct
  repack: fix typo in max-pack-size option
2014-01-27 10:45:49 -08:00
Jeff King
b861e235bc repack: propagate pack-objects options as strings
In the original shell version of git-repack, any options
destined for pack-objects were left as strings, and passed
as a whole. Since the C rewrite in commit a1bbc6c (repack:
rewrite the shell script in C, 2013-09-15), we now parse
these values to integers internally, then reformat the
integers when passing the option to pack-objects.

This has the advantage that we catch format errors earlier
(i.e., when repack is invoked, rather than when pack-objects
is invoked).

It has three disadvantages, though:

  1. Our internal data types may not be the right size. In
     the case of "--window-memory" and "--max-pack-size",
     these are "unsigned long" in pack-objects, but we can
     only represent a regular "int".

  2. Our parsing routines might not be the same as those of
     pack-objects. For the two options above, pack-objects
     understands "100m" to mean "100 megabytes", but repack
     does not.

  3. We have to keep a sentinel value to know whether it is
     worth passing the option along. In the case of
     "--window-memory", we currently do not pass it if the
     value is "0". But that is a meaningful value to
     pack-objects, where it overrides any configured value.

We can fix all of these by simply passing the strings from
the user along to pack-objects verbatim. This does not
actually fix anything for "--depth" or "--window", but these
are converted, too, for consistency.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-23 10:34:53 -08:00
Jeff King
aa8bd519db repack: make parsed string options const-correct
When we use OPT_STRING to parse an option, we get back a
pointer into the argv array, which should be "const char *".
The compiler doesn't notice because it gets passed through a
"void *" in the option struct.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-23 10:34:51 -08:00
Jeff King
44b96ecaa8 repack: fix typo in max-pack-size option
When we see "--max-pack-size", we accidentally propagated
this to pack-objects as "--max_pack_size", which does not
work at all.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-01-23 10:34:49 -08:00
Vicent Marti
5cf2741c5a repack: consider bitmaps when performing repacks
Since `pack-objects` will write a `.bitmap` file next to the `.pack` and
`.idx` files, this commit teaches `git-repack` to consider the new
bitmap indexes (if they exist) when performing repack operations.

This implies moving old bitmap indexes out of the way if we are
repacking a repository that already has them, and moving the newly
generated bitmap indexes into the `objects/pack` directory, next to
their corresponding packfiles.

Since `git repack` is now capable of handling these `.bitmap` files,
a normal `git gc` run on a repository that has `pack.writebitmaps` set
to true in its config file will generate bitmap indexes as part of the
garbage collection process.

Alternatively, `git repack` can be called with the `-b` switch to
explicitly generate bitmap indexes if you are experimenting
and don't want them on all the time.

Signed-off-by: Vicent Marti <tanoku@gmail.com>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-30 12:19:23 -08:00
Jeff King
b77fcd1edc repack: handle optional files created by pack-objects
We ask pack-objects to pack to a set of temporary files, and
then rename them into place. Some files that pack-objects
creates may be optional (like a .bitmap file), in which case
we would not want to call rename(). We already call stat()
and make the chmod optional if the file cannot be accessed.
We could simply skip the rename step in this case, but that
would be a minor regression in noticing problems with
non-optional files (like the .pack and .idx files).

Instead, we can now annotate extensions as optional, and
skip them if they don't exist (and otherwise rely on
rename() to barf).

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-30 12:19:23 -08:00
Jeff King
42a02d8529 repack: turn exts array into array-of-struct
This is slightly more verbose, but will let us annotate the
extensions with further options in future commits.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-30 12:19:23 -08:00
Jeff King
b328c2166e repack: stop using magic number for ARRAY_SIZE(exts)
We have a static array of extensions, but hardcode the size
of the array in our loops. Let's pull out this magic number,
which will make it easier to change.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-30 12:19:23 -08:00
Junio C Hamano
7794a680e6 Sync with 1.8.5.2
* maint:
  Git 1.8.5.2
  cmd_repack(): remove redundant local variable "nr_packs"
2013-12-17 14:12:17 -08:00
Michael Haggerty
3e7b066e22 cmd_repack(): remove redundant local variable "nr_packs"
Its value is the same as the number of entries in the "names"
string_list, so just use "names.nr" in its place.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Acked-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-17 10:54:41 -08:00
Christian Couder
5955654823 replace {pre,suf}fixcmp() with {starts,ends}_with()
Leaving only the function definitions and declarations so that any
new topic in flight can still make use of the old functions, replace
existing uses of the prefixcmp() and suffixcmp() with new API
functions.

The change can be recreated by mechanically applying this:

    $ git grep -l -e prefixcmp -e suffixcmp -- \*.c |
      grep -v strbuf\\.c |
      xargs perl -pi -e '
        s|!prefixcmp\(|starts_with\(|g;
        s|prefixcmp\(|!starts_with\(|g;
        s|!suffixcmp\(|ends_with\(|g;
        s|suffixcmp\(|!ends_with\(|g;
      '

on the result of preparatory changes in this series.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05 14:13:21 -08:00
Stefan Beller
0b63c6a5b7 repack: improve warnings about failure of renaming and removing files
Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-09-17 13:34:57 -07:00
Stefan Beller
ffc9329f48 repack: retain the return value of pack-objects
During the review process of the previous commit (repack: rewrite the
shell script in C), Johannes Sixt proposed to retain any exit codes from
the sub-process, which makes it probably more obvious in case of failure.

As the commit before should behave as close to the original shell
script, the proposed change is put in this extra commit.
The infrastructure however was already setup in the previous commit.
(Having a local 'ret' variable)

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-09-17 13:34:56 -07:00
Stefan Beller
a1bbc6c017 repack: rewrite the shell script in C
The motivation of this patch is to get closer to a goal of being
able to have a core subset of git functionality built in to git.
That would mean

 * people on Windows could get a copy of at least the core parts
   of Git without having to install a Unix-style shell

 * people using git in on servers with chrooted environments
   do not need to worry about standard tools lacking for shell
   scripts.

This patch is meant to be mostly a literal translation of the
git-repack script; the intent is that later patches would start using
more library facilities, but this patch is meant to be as close to a
no-op as possible so it doesn't do that kind of thing.

Signed-off-by: Stefan Beller <stefanbeller@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-09-17 13:34:50 -07:00