In `reprepare_packed_git()` we perform a couple of operations:
- We reload alternate object directories.
- We clear the loose object cache.
- We reprepare packfiles.
While the logic is hosted in "packfile.c", it clearly reaches into other
subsystems that aren't related to packfiles.
Split up the responsibility and introduce `odb_reprepare()` which now
becomes responsible for repreparing the whole object database. The
existing `reprepare_packed_git()` function is refactored accordingly and
only cares about reloading the packfile store now.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ps/object-store-midx-dedup-info:
midx: compute paths via their source
midx: stop duplicating info redundant with its owning source
midx: write multi-pack indices via their source
midx: load multi-pack indices via their source
midx: drop redundant `struct repository` parameter
odb: simplify calling `link_alt_odb_entry()`
odb: return newly created in-memory sources
odb: consistently use "dir" to refer to alternate's directory
odb: allow `odb_find_source()` to fail
odb: store locality in object database sources
Multi-pack indices store some information that is redundant with their
owning source:
- The locality bit that tracks whether the source is the primary
object source or an alternate.
- The object directory path the multi-pack index is located in.
- The pointer to the owning parent directory.
All of this information is already contained in `struct odb_source`. So
now that we always have that struct available when loading a multi-pack
index we have it readily accessible.
Drop the redundant information and instead store a pointer to the object
source.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Similar to the preceding commit, refactor the writing side of multi-pack
indices so that we pass in the object database source where the index
should be written to.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The config API had a set of convenience wrapper functions that
implicitly use the_repository instance; they have been removed and
inlined at the calling sites.
* ps/config-wo-the-repository: (21 commits)
config: fix sign comparison warnings
config: move Git config parsing into "environment.c"
config: remove unused `the_repository` wrappers
config: drop `git_config_set_multivar()` wrapper
config: drop `git_config_get_multivar_gently()` wrapper
config: drop `git_config_set_multivar_in_file_gently()` wrapper
config: drop `git_config_set_in_file_gently()` wrapper
config: drop `git_config_set()` wrapper
config: drop `git_config_set_gently()` wrapper
config: drop `git_config_set_in_file()` wrapper
config: drop `git_config_get_bool()` wrapper
config: drop `git_config_get_ulong()` wrapper
config: drop `git_config_get_int()` wrapper
config: drop `git_config_get_string()` wrapper
config: drop `git_config_get_string()` wrapper
config: drop `git_config_get_string_multi()` wrapper
config: drop `git_config_get_value()` wrapper
config: drop `git_config_get_value()` wrapper
config: drop `git_config_get()` wrapper
config: drop `git_config_clear()` wrapper
...
Redefine where the multi-pack-index sits in the object subsystem,
which recently was restructured to allow multiple backends that
support a single object source that belongs to one repository. A
midx does span mulitple "object sources".
* ps/object-store-midx:
midx: remove now-unused linked list of multi-pack indices
packfile: stop using linked MIDX list in `get_all_packs()`
packfile: stop using linked MIDX list in `find_pack_entry()`
packfile: refactor `get_multi_pack_index()` to work on sources
midx: stop using linked list when closing MIDX
packfile: refactor `prepare_packed_git_one()` to work on sources
midx: start tracking per object database source
* ps/object-store-midx:
midx: remove now-unused linked list of multi-pack indices
packfile: stop using linked MIDX list in `get_all_packs()`
packfile: stop using linked MIDX list in `find_pack_entry()`
packfile: refactor `get_multi_pack_index()` to work on sources
midx: stop using linked list when closing MIDX
packfile: refactor `prepare_packed_git_one()` to work on sources
midx: start tracking per object database source
In 036876a106 (config: hide functions using `the_repository` by
default, 2024-08-13) we have moved around a bunch of functions in the
config subsystem that depend on `the_repository`. Those function have
been converted into mere wrappers around their equivalent function that
takes in a repository as parameter, and the intent was that we'll
eventually remove those wrappers to make the dependency on the global
repository variable explicit at the callsite.
Follow through with that intent and remove `git_config()`. All callsites
are adjusted so that they use `repo_config(the_repository, ...)`
instead. While some callsites might already have a repository available,
this mechanical conversion is the exact same as the current situation
and thus cannot cause any regression. Those sites should eventually be
cleaned up in a later patch series.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"pack-objects" has been taught to avoid pointing into objects in
cruft packs from midx.
* tb/midx-avoid-cruft-packs:
repack: exclude cruft pack(s) from the MIDX where possible
pack-objects: introduce '--stdin-packs=follow'
pack-objects: swap 'show_{object,commit}_pack_hint'
pack-objects: fix typo in 'show_object_pack_hint()'
pack-objects: perform name-hash traversal for unpacked objects
pack-objects: declare 'rev_info' for '--stdin-packs' earlier
pack-objects: factor out handling '--stdin-packs'
pack-objects: limit scope in 'add_object_entry_from_pack()'
pack-objects: use standard option incompatibility functions
Code clean-up around object access API.
* ps/object-store:
odb: rename `read_object_with_reference()`
odb: rename `pretend_object_file()`
odb: rename `has_object()`
odb: rename `repo_read_object_file()`
odb: rename `oid_object_info()`
odb: trivial refactorings to get rid of `the_repository`
odb: get rid of `the_repository` when handling submodule sources
odb: get rid of `the_repository` when handling the primary source
odb: get rid of `the_repository` in `for_each()` functions
odb: get rid of `the_repository` when handling alternates
odb: get rid of `the_repository` in `odb_mkstemp()`
odb: get rid of `the_repository` in `assert_oid_type()`
odb: get rid of `the_repository` in `find_odb()`
odb: introduce parent pointers
object-store: rename files to "odb.{c,h}"
object-store: rename `object_directory` to `odb_source`
object-store: rename `raw_object_store` to `object_database`
The function `get_multi_pack_index()` loads multi-pack indices via
`prepare_packed_git()` and then returns the linked list of multi-pack
indices that is stored in `struct object_database`. That list is in the
process of being removed though in favor of storing the MIDX as part of
the object database source it belongs to.
Refactor `get_multi_pack_index()` so that it returns the multi-pack
index for a single object source. Callers are now expected to call this
function for each source they are interested in. This requires them to
iterate through alternates, so we have to prepare alternate object
sources before doing so.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* tb/midx-avoid-cruft-packs:
repack: exclude cruft pack(s) from the MIDX where possible
pack-objects: introduce '--stdin-packs=follow'
pack-objects: swap 'show_{object,commit}_pack_hint'
pack-objects: fix typo in 'show_object_pack_hint()'
pack-objects: perform name-hash traversal for unpacked objects
pack-objects: declare 'rev_info' for '--stdin-packs' earlier
pack-objects: factor out handling '--stdin-packs'
pack-objects: limit scope in 'add_object_entry_from_pack()'
pack-objects: use standard option incompatibility functions
* ps/object-store:
odb: rename `read_object_with_reference()`
odb: rename `pretend_object_file()`
odb: rename `has_object()`
odb: rename `repo_read_object_file()`
odb: rename `oid_object_info()`
odb: trivial refactorings to get rid of `the_repository`
odb: get rid of `the_repository` when handling submodule sources
odb: get rid of `the_repository` when handling the primary source
odb: get rid of `the_repository` in `for_each()` functions
odb: get rid of `the_repository` when handling alternates
odb: get rid of `the_repository` in `odb_mkstemp()`
odb: get rid of `the_repository` in `assert_oid_type()`
odb: get rid of `the_repository` in `find_odb()`
odb: introduce parent pointers
object-store: rename files to "odb.{c,h}"
object-store: rename `object_directory` to `odb_source`
object-store: rename `raw_object_store` to `object_database`
The 'extensions.preciousObjects' setting when set true, prevents
operations that might drop objects from the object storage. This setting
is populated in the global variable
'repository_format_precious_objects'.
Move this global variable to repo scope by adding it to 'struct
repository and also refactor all the occurences accordingly.
This change is part of an ongoing effort to eliminate global variables,
improve modularity and help libify the codebase.
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Ghanshyam Thakkar <shyamthakkar001@gmail.com>
Signed-off-by: Ayush Chandekar <ayu.chandekar@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Rename `oid_object_info()` to `odb_read_object_info()` as well as their
`_extended()` variant to match other functions related to the object
database and our modern coding guidelines.
Introduce compatibility wrappers so that any in-flight topics will
continue to compile.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The functions to manage alternates all depend on `the_repository`.
Refactor them to accept an object database as a parameter and adjust all
callers. The functions are renamed accordingly.
Note that right now the situation is still somewhat weird because we end
up using the object store path provided by the object store's repository
anyway. Consequently, we could have instead passed in a pointer to the
repository instead of passing in the pointer to the object store. This
will be addressed in subsequent commits though, where we will start to
use the path owned by the object store itself.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In the preceding commits we have renamed the structures contained in
"object-store.h" to `struct object_database` and `struct odb_backend`.
As such, the code files "object-store.{c,h}" are confusingly named now.
Rename them to "odb.{c,h}" accordingly.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In ddee3703b3 (builtin/repack.c: add cruft packs to MIDX during
geometric repack, 2022-05-20), repack began adding cruft pack(s) to the
MIDX with '--write-midx' to ensure that the resulting MIDX was always
closed under reachability in order to generate reachability bitmaps.
While the previous patch added the '--stdin-packs=follow' option to
pack-objects, it is not yet on by default. Given that, suppose you have
a once-unreachable object packed in a cruft pack, which later becomes
reachable from one or more objects in a geometrically repacked pack.
That once-unreachable object *won't* appear in the new pack, since the
cruft pack was not specified as included or excluded when the
geometrically repacked pack was created with 'pack-objects
--stdin-packs' (*not* '--stdin-packs=follow', which is not on). If that
new pack is included in a MIDX without the cruft pack, then trying to
generate bitmaps for that MIDX may fail. This happens when the bitmap
selection process picks one or more commits which reach the
once-unreachable objects.
To mitigate this failure mode, commit ddee3703b3 ensures that the MIDX
will be closed under reachability by including cruft pack(s). If cruft
pack(s) were not included, we would fail to generate a MIDX bitmap. But
ddee3703b3 alludes to the fact that this is sub-optimal by saying
[...] it's desirable to avoid including cruft packs in the MIDX
because it causes the MIDX to store a bunch of objects which are
likely to get thrown away.
, which is true, but hides an even larger problem. If repositories
rarely prune their unreachable objects and/or have many of them, the
MIDX must keep track of a large number of objects which bloats the MIDX
and slows down object lookup.
This is doubly unfortunate because the vast majority of objects in cruft
pack(s) are unlikely to be read. But any object lookups that go through
the MIDX must binary search over them anyway, slowing down object
lookups using the MIDX.
This patch causes geometrically-repacked packs to contain a copy of any
once-unreachable object(s) with 'git pack-objects --stdin-packs=follow',
allowing us to avoid including any cruft packs in the MIDX. This is
because a sequence of geometrically-repacked packs that were all
generated with '--stdin-packs=follow' are guaranteed to have their union
be closed under reachability.
Note that you cannot guarantee that a collection of packs is closed
under reachability if not all of them were generated with "following" as
above. One tell-tale sign that not all geometrically-repacked packs in
the MIDX were generated with "following" is to see if there is a pack in
the existing MIDX that is not going to be somehow represented (either
verbatim or as part of a geometric rollup) in the new MIDX.
If there is, then starting to generate packs with "following" during
geometric repacking won't work, since it's open to the same race as
described above.
But if you're starting from scratch (e.g., building the first MIDX after
an all-into-one '--cruft' repack), then you can guarantee that the union
of subsequently generated packs from geometric repacking *is* closed
under reachability.
(One exception here is when "starting from scratch" results in a noop
repack, e.g., because the non-cruft pack(s) in a repository already form
a geometric progression. Since we can't tell whether or not those were
generated with '--stdin-packs=follow', they may depend on
once-unreachable objects, so we have to include the cruft pack in the
MIDX in this case.)
Detect when this is the case and avoid including cruft packs in the MIDX
where possible. The existing behavior remains the default, and the new
behavior is available with the config 'repack.midxMustIncludeCruft' set
to 'false'.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git pack-objects" learns to find delta bases from blobs at the
same path, using the --path-walk API.
* ds/path-walk-2:
pack-objects: allow --shallow and --path-walk
path-walk: add new 'edge_aggressive' option
pack-objects: thread the path-based compression
pack-objects: refactor path-walk delta phase
scalar: enable path-walk during push via config
pack-objects: enable --path-walk via config
repack: add --path-walk option
t5538: add tests to confirm deltas in shallow pushes
pack-objects: introduce GIT_TEST_PACK_PATH_WALK
p5313: add performance tests for --path-walk
pack-objects: update usage to match docs
pack-objects: add --path-walk option
pack-objects: extract should_attempt_deltas()
Since 'git pack-objects' supports a --path-walk option, allow passing it
through in 'git repack'. This presents interesting testing opportunities for
comparing the different repacking strategies against each other.
Add the --path-walk option to the performance tests in p5313.
For the microsoft/fluentui repo [1] checked out at a specific commit [2],
the --path-walk tests in p5313 look like this:
Test this tree
-------------------------------------------------------------------------
5313.18: thin pack with --path-walk 0.08(0.06+0.02)
5313.19: thin pack size with --path-walk 18.4K
5313.20: big pack with --path-walk 2.10(7.80+0.26)
5313.21: big pack size with --path-walk 19.8M
5313.22: shallow fetch pack with --path-walk 1.62(3.38+0.17)
5313.23: shallow pack size with --path-walk 33.6M
5313.24: repack with --path-walk 81.29(96.08+0.71)
5313.25: repack size with --path-walk 142.5M
[1] https://github.com/microsoft/fluentui
[2] e70848ebac1cd720875bccaa3026f4a9ed700e08
Along with the earlier tests in p5313, I'll instead reformat the
comparison as follows:
Repack Method Pack Size Time
---------------------------------------
Hash v1 439.4M 87.24s
Hash v2 161.7M 21.51s
Path Walk 142.5M 81.29s
There are a few things to notice here:
1. The benefits of --name-hash-version=2 over --name-hash-version=1 are
significant, but --path-walk still compresses better than that
option.
2. The --path-walk command is still using --name-hash-version=1 for the
second pass of delta computation, using the increased name hash
collisions as a potential method for opportunistic compression on
top of the path-focused compression.
3. The --path-walk algorithm is currently sequential and does not use
multiple threads for delta compression. Threading will be
implemented in a future change so the computation time will improve
to better compete in this metric.
There are small benefits in size for my copy of the Git repository:
Repack Method Pack Size Time
---------------------------------------
Hash v1 248.8M 30.44s
Hash v2 249.0M 30.15s
Path Walk 213.2M 142.50s
As well as in the nodejs/node repository [3]:
Repack Method Pack Size Time
---------------------------------------
Hash v1 739.9M 71.18s
Hash v2 764.6M 67.82s
Path Walk 698.1M 208.10s
[3] https://github.com/nodejs/node
This benefit also repeats in my copy of the Linux kernel repository:
Repack Method Pack Size Time
---------------------------------------
Hash v1 2.5G 554.41s
Hash v2 2.5G 549.62s
Path Walk 2.2G 1562.36s
It is important to see that even when the repository shape does not have
many name-hash collisions, there is a slight space boost to be found
using this method.
As this repacking strategy was released in Git for Windows 2.47.0, some
users have reported cases where the --path-walk compression is slightly
worse than the --name-hash-version=2 option. In those cases, it may be
beneficial to combine the two options. However, there has not been a
released version of Git that has both options and I don't have access to
these repos for testing.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Update parse-options API to catch mistakes to pass address of an
integral variable of a wrong type/size.
* ps/parse-options-integers:
parse-options: detect mismatches in integer signedness
parse-options: introduce precision handling for `OPTION_UNSIGNED`
parse-options: introduce precision handling for `OPTION_INTEGER`
parse-options: rename `OPT_MAGNITUDE()` to `OPT_UNSIGNED()`
parse-options: support unit factors in `OPT_INTEGER()`
global: use designated initializers for options
parse: fix off-by-one for minimum signed values
With the preceding commit, `OPT_INTEGER()` has learned to support unit
factors. Consequently, the major differencen between `OPT_INTEGER()` and
`OPT_MAGNITUDE()` isn't the support of unit factors anymore, as both of
them do support them now. Instead, the difference is that one handles
signed and the other handles unsigned integers.
Adapt the name of `OPT_MAGNITUDE()` accordingly by renaming it to
`OPT_UNSIGNED()`.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The "object-store-ll.h" header has been introduced to keep transitive
header dependendcies and compile times at bay. Now that we have created
a new "object-store.c" file though we can easily move the last remaining
additional bit of "object-store.h", the `odb_path_map`, out of the
header.
Do so. As the "object-store.h" header is now equivalent to its low-level
alternative we drop the latter and inline it into the former.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The previous commit changed the behavior of repack's '--max-cruft-size'
to specify a cruft pack-specific override for '--max-pack-size'.
Introduce a new flag, '--combine-cruft-below-size' which is a
replacement for the old behavior of '--max-cruft-size'. This new flag
does explicitly what it says: it combines together cruft packs which are
smaller than a given threshold, and leaves alone ones which are
larger.
This accomplishes the original intent of '--max-cruft-size', which was
to avoid repacking cruft packs larger than the given threshold.
The new behavior is slightly different. Instead of building up small
packs together until the threshold is met, '--combine-cruft-below-size'
packs up *all* cruft packs smaller than the threshold. This means that
we may make a pack much larger than the given threshold (e.g., if you
aggregate 5 packs which are each 99 MiB in size with a threshold of 100
MiB).
But that's OK: the point isn't to restrict the size of the cruft packs
we generate, it's to avoid working with ones that have already grown too
large. If repositories still want to limit the size of the generated
cruft pack(s), they may use '--max-cruft-size'.
There's some minor test fallout as a result of the slight differences in
behavior between the old meaning of '--max-cruft-size' and the behavior
of '--combine-cruft-below-size'. In the test which is now called
"--combine-cruft-below-size combines packs", we need to use the new flag
over the old one to exercise that test's intended behavior. The
remainder of the changes there are to improve the clarity of the
comments.
Suggested-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 37dc6d8104 (builtin/repack.c: implement support for
`--max-cruft-size`, 2023-10-02), we exposed new functionality that
allowed repositories to specify the behavior of when we should combine
multiple cruft packs together.
This feature was designed to ensure that we never repacked cruft packs
which were larger than the given threshold in order to provide tighter
I/O bounds for repositories that have many unreachable objects. In
essence, specifying '--max-cruft-size=N' instructed 'repack' to
aggregate cruft packs together (in order of ascending size) until the
combine size grows past 'N', and then make a new cruft pack whose
contents includes the packs we rolled up.
But this isn't quite how it works in practice. Suppose for example that
we have two cruft packs which are each 100MiB in size. One might expect
specifying "--max-cruft-size=200M" would combine these two packs
together, and then avoid repacking them until a pruning GC takes place.
In reality, 'repack' would try and aggregate these together, but writing
a pack that is strictly smaller than 200 MiB (since pack-objects'
"--max-pack-size" provides a strict bound for packs containing more than
one object).
So instead we'll write out a pack that is, say, 199 MiB in size, and
then another 1 MiB pack containing the balance. If we later repack the
repository without adding any new unreachable objects, we'll repeat the
same exercise again, making the same 199 MiB and 1 MiB packs each time.
This happens because of a poor choice to bolt the '--max-cruft-size'
functionality onto pack-objects' '--max-pack-size', forcing us to
generate packs which are always smaller than the provided threshold and
thus subject to repacking.
The following commit will introduce a new flag that implements something
similar to the behavior above. Let's prepare for that by making repack's
'--max-cruft-size' flag behave as an cruft pack-specific override for
'--max-pack-size'.
Do so by temporarily repurposing the 'collapse_small_cruft_packs()'
function to instead generate a cruft pack using the same instructions as
if we didn't specify any maximum pack size. The calling code looks
something like:
if (args->max_pack_size && !cruft_expiration) {
collapse_small_cruft_packs(in, args->max_pack_size, existing);
} else {
for_each_string_list_item(item, &existing->non_kept_packs)
fprintf(in, "-%s.pack\n", item->string);
for_each_string_list_item(item, &existing->cruft_packs)
fprintf(in, "-%s.pack\n", item->string);
}
This patch makes collapse_small_cruft_packs() behave identically to the
'else' arm of the conditional above. This repurposing of
'collapse_small_cruft_packs()' is intentional, since it will set us up
nicely to introduce the new behavior in the following commit.
Naturally, there is some test fallout in the test which exercises the
old meaning of '--max-cruft-size'. Mark that test as failing for now to
be dealt with in the following commit. Likewise, add a new test which
explicitly tests the behavior of '--max-cruft-size' to place a hard
limit on the size of any generated cruft pack(s).
Note that this is a breaking change, as it alters the user-visible
behavior of '--max-cruft-size'. But I'm OK changing this behavior in
this instance, since the behavior wasn't accurate to begin with.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Acked-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git repack --keep-unreachable" to send unreachable objects to the
main pack "git repack -ad" produces did not work when there is no
existing packs, which has been corrected.
* ps/repack-keep-unreachable-in-unpacked-repo:
builtin/repack: fix `--keep-unreachable` when there are no packs
"git pack-objects" and its wrapper "git repack" learned an option
to use an alternative path-hash function to improve delta-base
selection to produce a packfile with deeper history than window
size.
* ds/name-hash-tweaks:
pack-objects: prevent name hash version change
test-tool: add helper for name-hash values
p5313: add size comparison test
pack-objects: add GIT_TEST_NAME_HASH_VERSION
repack: add --name-hash-version option
pack-objects: add --name-hash-version option
pack-objects: create new name-hash function version
The "--keep-unreachable" flag is supposed to append any unreachable
objects to the newly written pack. This flag is explicitly documented as
appending both packed and loose unreachable objects to the new packfile.
And while this works alright when repacking with preexisting packfiles,
it stops working when the repository does not have any packfiles at all.
The root cause are the conditions used to decide whether or not we want
to append "--pack-loose-unreachable" to git-pack-objects(1). There are
a couple of conditions here:
- `has_existing_non_kept_packs()` checks whether there are existing
packfiles. This condition makes sense to guard "--keep-pack=",
"--unpack-unreachable" and "--keep-unreachable", because all of
these flags only make sense in combination with existing packfiles.
But it does not make sense to disable `--pack-loose-unreachable`
when there aren't any preexisting packfiles, as loose objects can be
packed into the new packfile regardless of that.
- `delete_redundant` checks whether we want to delete any objects or
packs that are about to become redundant. The documentation of
`--keep-unreachable` explicitly says that `git repack -ad` needs to
be executed for the flag to have an effect.
It is not immediately obvious why such redundant objects need to be
deleted in order for "--pack-unreachable-objects" to be effective.
But as things are working as documented this is nothing we'll change
for now.
- `pack_everything & PACK_CRUFT` checks that we're not creating a
cruft pack. This condition makes sense in the context of
"--pack-loose-unreachable", as unreachable objects would end up in
the cruft pack anyway.
So while the second and third condition are sensible, it does not make
any sense to condition `--pack-loose-unreachable` on the existence of
packfiles.
Fix the bug by splitting out the "--pack-loose-unreachable" and only
making it depend on the second and third condition. Like this, loose
unreachable objects will be packed regardless of any preexisting
packfiles.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The new '--name-hash-version' option for 'git repack' is a simple
pass-through to the underlying 'git pack-objects' subcommand. However,
this subcommand may have other options and a temporary filename as part
of the subcommand execution that may not be predictable or could change
over time.
The existing test_subcommand method requires an exact list of arguments
for the subcommand. This is too rigid for our needs here, so create a
new method, test_subcommand_flex. Use it to check that the
--name-hash-version option is passing through.
Since we are modifying the 'git repack' command, let's bring its usage
in line with the Documentation's synopsis. This removes it from the
allow list in t0450 so it will remain in sync in the future.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Start working to make the codebase buildable with -Wsign-compare.
* ps/build-sign-compare:
t/helper: don't depend on implicit wraparound
scalar: address -Wsign-compare warnings
builtin/patch-id: fix type of `get_one_patchid()`
builtin/blame: fix type of `length` variable when emitting object ID
gpg-interface: address -Wsign-comparison warnings
daemon: fix type of `max_connections`
daemon: fix loops that have mismatching integer types
global: trivial conversions to fix `-Wsign-compare` warnings
pkt-line: fix -Wsign-compare warning on 32 bit platform
csum-file: fix -Wsign-compare warning on 32-bit platform
diff.h: fix index used to loop through unsigned integer
config.mak.dev: drop `-Wno-sign-compare`
global: mark code units that generate warnings with `-Wsign-compare`
compat/win32: fix -Wsign-compare warning in "wWinMain()"
compat/regex: explicitly ignore "-Wsign-compare" warnings
git-compat-util: introduce macros to disable "-Wsign-compare" warnings
Stop using `the_repository` in the "server-info" subsystem by passing in
a repository when updating server info and storing the repository in the
`update_info_ctx` structure to make it accessible to other functions.
Adjust callers accordingly by using `the_repository`. While there may be
some callers that have a repository available in their context, this
trivial conversion allows for easier verification and bubbles up the use
of `the_repository` by one level.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
* ps/build-sign-compare:
t/helper: don't depend on implicit wraparound
scalar: address -Wsign-compare warnings
builtin/patch-id: fix type of `get_one_patchid()`
builtin/blame: fix type of `length` variable when emitting object ID
gpg-interface: address -Wsign-comparison warnings
daemon: fix type of `max_connections`
daemon: fix loops that have mismatching integer types
global: trivial conversions to fix `-Wsign-compare` warnings
pkt-line: fix -Wsign-compare warning on 32 bit platform
csum-file: fix -Wsign-compare warning on 32-bit platform
diff.h: fix index used to loop through unsigned integer
config.mak.dev: drop `-Wno-sign-compare`
global: mark code units that generate warnings with `-Wsign-compare`
compat/win32: fix -Wsign-compare warning in "wWinMain()"
compat/regex: explicitly ignore "-Wsign-compare" warnings
git-compat-util: introduce macros to disable "-Wsign-compare" warnings
Mark code units that generate warnings with `-Wsign-compare`. This
allows for a structured approach to get rid of all such warnings over
time in a way that can be easily measured.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In a previous commit, we passed the repository field to all
subcommands in the `builtin/` directory. Utilize this to pass the
repository field down to the `write_midx_file[_only]` functions to
remove the usage of `the_repository` global variables.
With this, all usage of global variables in `midx-write.c` is removed,
hence, remove the `USE_THE_REPOSITORY_VARIABLE` guard from the file.
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The function `for_each_packed_object` currently relies on the global
variable `the_repository`. To eliminate global variable usage in
`packfile.c`, we should progressively shift the dependency on
the_repository to higher layers. Let's remove its usage from this
function and closely related function `is_promisor_object`.
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When repacking, we assemble git-pack-objects(1) arguments both for the
"normal" pack and for the cruft pack. This configuration gets populated
with a bunch of `OPT_PASSTHRU` options that we end up passing to the
child process. These options are allocated, but never free'd.
Create a new `pack_objects_args_release()` function that releases the
memory for us and call it for both sets of options.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The convention to calling into built-in command implementation has
been updated to pass the repository, if known, together with the
prefix value.
* jc/pass-repo-to-builtins:
add: pass in repo variable instead of global the_repository
builtin: remove USE_THE_REPOSITORY for those without the_repository
builtin: remove USE_THE_REPOSITORY_VARIABLE from builtin.h
builtin: add a repository parameter for builtin functions
Code clean-up.
* ps/environ-wo-the-repository: (21 commits)
environment: stop storing "core.notesRef" globally
environment: stop storing "core.warnAmbiguousRefs" globally
environment: stop storing "core.preferSymlinkRefs" globally
environment: stop storing "core.logAllRefUpdates" globally
refs: stop modifying global `log_all_ref_updates` variable
branch: stop modifying `log_all_ref_updates` variable
repo-settings: track defaults close to `struct repo_settings`
repo-settings: split out declarations into a standalone header
environment: guard state depending on a repository
environment: reorder header to split out `the_repository`-free section
environment: move `set_git_dir()` and related into setup layer
environment: make `get_git_namespace()` self-contained
environment: move object database functions into object layer
config: make dependency on repo in `read_early_config()` explicit
config: document `read_early_config()` and `read_very_early_config()`
environment: make `get_git_work_tree()` accept a repository
environment: make `get_graft_file()` accept a repository
environment: make `get_index_file()` accept a repository
environment: make `get_object_directory()` accept a repository
environment: make `get_git_common_dir()` accept a repository
...
Instead of including USE_THE_REPOSITORY_VARIABLE by default on every
builtin, remove it from builtin.h and add it to all the builtins that
include builtin.h (by definition, that means all builtins/*.c).
Also, remove the include statement for repository.h since it gets
brought in through builtin.h.
The next step will be to migrate each builtin
from having to use the_repository.
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to reduce the usage of the global the_repository, add a
parameter to builtin functions that will get passed a repository
variable.
This commit uses UNUSED on most of the builtin functions, as subsequent
commits will modify the actual builtins to pass the repository parameter
down.
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `get_object_directory()` function retrieves the path to the object
directory for `the_repository`. Make it accept a `struct repository`
such that it can work on arbitrary repositories and make it part of the
repository subsystem. This reduces our reliance on `the_repository` and
clarifies scope.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The list of packs to keep is populated via a command line option but
never free'd. Plug this memory leak.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In `repack_promisor_objects()` we read output from git-pack-objects(1)
line by line, using `strbuf_getline_lf()`. We never free the line
buffer, causing a memory leak. Plug it.
This leak is being hit in t5616, but plugging it alone is not
sufficient to make the whole test suite leak free.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When writing an MIDX in git-repack(1) we first collect all the pack
names that we want to add to it in a string list. This list is marked as
`NODUP`, which indicates that it will neither duplicate nor own strings
added to it. In `write_midx_included_packs()` we then `insert()` strings
via `xstrdup()` or `strbuf_detach()`, but the resulting strings will not
be owned by anything and thus leak.
Fix this issue by marking the list as `DUP` and using a local buffer to
compute the pack names.
This leak is hit in t5319, but plugging it is not sufficient to make the
whole test suite pass.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Add a parameter to each_ref_fn so that callers to the ref APIs
that use this function as a callback can have acess to the
unresolved value of a symbolic ref.
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Now that the rest of the MIDX subsystem and relevant callers have been
updated to learn about how to read and process incremental MIDX chains,
let's finally update the implementation in `write_midx_internal()` to be
able to write incremental MIDX chains.
This new feature is available behind the `--incremental` option for the
`multi-pack-index` builtin, like so:
$ git multi-pack-index write --incremental
The implementation for doing so is relatively straightforward, and boils
down to a handful of different kinds of changes implemented in this
patch:
- The `compute_sorted_entries()` function is taught to reject objects
which appear in any existing MIDX layer.
- Functions like `write_midx_revindex()` are adjusted to write
pack_order values which are offset by the number of objects in the
base MIDX layer.
- The end of `write_midx_internal()` is adjusted to move
non-incremental MIDX files when necessary (i.e. when creating an
incremental chain with an existing non-incremental MIDX in the
repository).
There are a handful of other changes that are introduced, like new
functions to clear incremental MIDX files that are unrelated to the
current chain (using the same "keep_hash" mechanism as in the
non-incremental case).
The tests explicitly exercising the new incremental MIDX feature are
relatively limited for two reasons:
1. Most of the "interesting" behavior is already thoroughly covered in
t5319-multi-pack-index.sh, which handles the core logic of reading
objects through a MIDX.
The new tests in t5334-incremental-multi-pack-index.sh are mostly
focused on creating and destroying incremental MIDXs, as well as
stitching their results together across layers.
2. A new GIT_TEST environment variable is added called
"GIT_TEST_MULTI_PACK_INDEX_WRITE_INCREMENTAL", which modifies the
entire test suite to write incremental MIDXs after repacking when
combined with the "GIT_TEST_MULTI_PACK_INDEX" variable.
This exercises the long tail of other interesting behavior that is
defined implicitly throughout the rest of the CI suite. It is
likewise added to the linux-TEST-vars job.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Two years ago, commit ff1e653c8e (midx: respect
'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP', 2021-08-31) introduced a new
environment variable which caused the test suite to write MIDX bitmaps
after any 'git repack' invocation.
At the time, this was done to help flush out any bugs with MIDX bitmaps
that weren't explicitly covered in the t5326-multi-pack-bitmap.sh
script.
Two years later, that flag has served us well and is no longer providing
meaningful coverage, as the script in t5326 has matured substantially
and covers many more interesting cases than it did back when ff1e653c8e
was originally written.
Remove the 'GIT_TEST_MULTI_PACK_INDEX_WRITE_BITMAP' environment variable
as it is no longer serving a useful purpose. More importantly, removing
this variable clears the way for us to introduce a new one to help
similarly flush out bugs related to incremental MIDX chains.
Because these incremental MIDX chains are (for now) incompatible with
MIDX bitmaps, we cannot have both.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Leakfixes.
* ps/leakfixes:
builtin/mv: fix leaks for submodule gitfile paths
builtin/mv: refactor to use `struct strvec`
builtin/mv duplicate string list memory
builtin/mv: refactor `add_slash()` to always return allocated strings
strvec: add functions to replace and remove strings
submodule: fix leaking memory for submodule entries
commit-reach: fix memory leak in `ahead_behind()`
builtin/credential: clear credential before exit
config: plug various memory leaks
config: clarify memory ownership in `git_config_string()`
builtin/log: stop using globals for format config
builtin/log: stop using globals for log config
convert: refactor code to clarify ownership of check_roundtrip_encoding
diff: refactor code to clarify memory ownership of prefixes
config: clarify memory ownership in `git_config_pathname()`
http: refactor code to clarify memory ownership
checkout: clarify memory ownership in `unique_tracking_name()`
strbuf: fix leak when `appendwholeline()` fails with EOF
transport-helper: fix leaking helper name
The out parameter of `git_config_string()` is a `const char **` even
though we transfer ownership of memory to the caller. This is quite
misleading and has led to many memory leaks all over the place. Adapt
the parameter to instead be `char **`.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Both `peel_object()` and `peel_iterated_oid()` implicitly rely on
`the_repository` to look up objects. Despite the fact that we want to
get rid of `the_repository`, it also leads to some restrictions in our
ref iterators when trying to retrieve the peeled value for a repository
other than `the_repository`.
Refactor these functions such that both take a repository as argument
and remove the now-unnecessary restrictions.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Apply the rules that rewrite callers of "refs" interfaces to explicitly
pass `struct ref_store`. The resulting patch has been applied with the
`--whitespace=fix` option.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When "git repack" repacks promisor objects, it starts a pack-objects
subprocess and uses xwrite() to send object names over the pipe to
it, but without any error checking. An I/O error or short write
(even though a short write is unlikely for such a small amount of
data) can result in a packfile that lacks certain objects we wanted
to put in there, leading to a silent repository corruption.
Use write_in_full(), instead of xwrite(), to mitigate short write
risks, check errors from it, and abort if we see a failure.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Remove unused header "#include".
* en/header-cleanup:
treewide: remove unnecessary includes in source files
treewide: add direct includes currently only pulled in transitively
trace2/tr2_tls.h: remove unnecessary include
submodule-config.h: remove unnecessary include
pkt-line.h: remove unnecessary include
line-log.h: remove unnecessary include
http.h: remove unnecessary include
fsmonitor--daemon.h: remove unnecessary includes
blame.h: remove unnecessary includes
archive.h: remove unnecessary include
treewide: remove unnecessary includes in source files
treewide: remove unnecessary includes from header files
Each of these were checked with
gcc -E -I. ${SOURCE_FILE} | grep ${HEADER_FILE}
to ensure that removing the direct inclusion of the header actually
resulted in that header no longer being included at all (i.e. that
no other header pulled it in transitively).
...except for a few cases where we verified that although the header
was brought in transitively, nothing from it was directly used in
that source file. These cases were:
* builtin/credential-cache.c
* builtin/pull.c
* builtin/send-pack.c
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The repack option --keep-unreachable is incompatible with -A, --cruft is
incompatible with -A and -k, and -k is short for --keep-unreachable. So
they are all incompatible with each other.
Use the function for checking three mutually incompatible options,
die_for_incompatible_opt3(), to perform this check in one place and
without repetition. This is shorter and clearer.
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git repack" learned "--max-cruft-size" to prevent cruft packs from
growing without bounds.
* tb/repack-max-cruft-size:
repack: free existing_cruft array after use
builtin/repack.c: avoid making cruft packs preferred
builtin/repack.c: implement support for `--max-cruft-size`
builtin/repack.c: parse `--max-pack-size` with OPT_MAGNITUDE
t7700: split cruft-related tests to t7704
We allocate an array of packed_git pointers so that we can sort the list
of cruft packs, but we never free the array, causing a small leak. Note
that we don't need to free the packed_git structs themselves; they're
owned by the repository object.
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When doing a `--geometric` repack, we make sure that the preferred pack
(if writing a MIDX) is the largest pack that we *didn't* repack. That
has the effect of keeping the preferred pack in sync with the pack
containing a majority of the repository's reachable objects.
But if the repository happens to double in size, we'll repack
everything. Here we don't specify any `--preferred-pack`, and instead
let the MIDX code choose.
In the past, that worked fine, since there would only be one pack to
choose from: the one we just wrote. But it's no longer necessarily the
case that there is one pack to choose from. It's possible that the
repository also has a cruft pack, too.
If the cruft pack happens to come earlier in lexical order (and has an
earlier mtime than any non-cruft pack), we'll pick that pack as
preferred. This makes it impossible to reuse chunks of the reachable
pack verbatim from pack-objects, so is sub-optimal.
Luckily, this is a somewhat rare circumstance to be in, since we would
have to repack the entire repository during a `--geometric` repack, and
the cruft pack would have to sort ahead of the pack we just created.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Cruft packs are an alternative mechanism for storing a collection of
unreachable objects whose mtimes are recent enough to avoid being
pruned out of the repository.
When cruft packs were first introduced back in b757353676
(builtin/pack-objects.c: --cruft without expiration, 2022-05-20) and
a7d493833f (builtin/pack-objects.c: --cruft with expiration,
2022-05-20), the recommended workflow consisted of:
- Repacking periodically, either by packing anything loose in the
repository (via `git repack -d`) or producing a geometric sequence
of packs (via `git repack --geometric=<d> -d`).
- Every so often, splitting the repository into two packs, one cruft
to store the unreachable objects, and another non-cruft pack to
store the reachable objects.
Repositories may (out of band with the above) choose periodically to
prune out some unreachable objects which have aged out of the grace
period by generating a pack with `--cruft-expiration=<approxidate>`.
This allowed repositories to maintain relatively few packs on average,
and quarantine unreachable objects together in a cruft pack, avoiding
the pitfalls of holding unreachable objects as loose while they age out
(for more, see some of the details in 3d89a8c118
(Documentation/technical: add cruft-packs.txt, 2022-05-20)).
This all works, but can be costly from an I/O-perspective when
frequently repacking a repository that has many unreachable objects.
This problem is exacerbated when those unreachable objects are rarely
(if every) pruned.
Since there is at most one cruft pack in the above scheme, each time we
update the cruft pack it must be rewritten from scratch. Because much of
the pack is reused, this is a relatively inexpensive operation from a
CPU-perspective, but is very costly in terms of I/O since we end up
rewriting basically the same pack (plus any new unreachable objects that
have entered the repository since the last time a cruft pack was
generated).
At the time, we decided against implementing more robust support for
multiple cruft packs. This patch implements that support which we were
lacking.
Introduce a new option `--max-cruft-size` which allows repositories to
accumulate cruft packs up to a given size, after which point a new
generation of cruft packs can accumulate until it reaches the maximum
size, and so on. To generate a new cruft pack, the process works like
so:
- Sort a list of any existing cruft packs in ascending order of pack
size.
- Starting from the beginning of the list, group cruft packs together
while the accumulated size is smaller than the maximum specified
pack size.
- Combine the objects in these cruft packs together into a new cruft
pack, along with any other unreachable objects which have since
entered the repository.
Once a cruft pack grows beyond the size specified via `--max-cruft-size`
the pack is effectively frozen. This limits the I/O churn up to a
quadratic function of the value specified by the `--max-cruft-size`
option, instead of behaving quadratically in the number of total
unreachable objects.
When pruning unreachable objects, we bypass the new code paths which
combine small cruft packs together, and instead start from scratch,
passing in the appropriate `--max-pack-size` down to `pack-objects`,
putting it in charge of keeping the resulting set of cruft packs sized
correctly.
This may seem like further I/O churn, but in practice it isn't so bad.
We could prune old cruft packs for whom all or most objects are removed,
and then generate a new cruft pack with just the remaining set of
objects. But this additional complexity buys us relatively little,
because most objects end up being pruned anyway, so the I/O churn is
well contained.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The repack builtin takes a `--max-pack-size` command-line argument which
it uses to feed into any of the pack-objects children that it may spawn
when generating a new pack.
This option is parsed with OPT_STRING, meaning that we'll accept
anything as input, punting on more fine-grained validation until we get
down into pack-objects.
This is fine, but it's wasteful to spend an entire sub-process just to
figure out that one of its option is bogus. Instead, parse the value of
`--max-pack-size` with OPT_MAGNITUDE in 'git repack', and then pass the
known-good result down to pack-objects.
Suggested-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
A previous commit has implemented `git repack --filter=<filter-spec>` to
allow users to filter out some objects from the main pack and move them
into a new different pack.
It would be nice if this new different pack could be created in a
different directory than the regular pack. This would make it possible
to move large blobs into a pack on a different kind of storage, for
example cheaper storage.
Even in a different directory, this pack can be accessible if, for
example, the Git alternates mechanism is used to point to it. In fact
not using the Git alternates mechanism can corrupt a repo as the
generated pack containing the filtered objects might not be accessible
from the repo any more. So setting up the Git alternates mechanism
should be done before using this feature if the user wants the repo to
be fully usable while this feature is used.
In some cases, like when a repo has just been cloned or when there is no
other activity in the repo, it's Ok to setup the Git alternates
mechanism afterwards though. It's also Ok to just inspect the generated
packfile containing the filtered objects and then just move it into the
'.git/objects/pack/' directory manually. That's why it's not necessary
for this command to check that the Git alternates mechanism has been
already setup.
While at it, as an example to show that `--filter` and `--filter-to`
work well with other options, let's also add a test to check that these
options work well with `--max-pack-size`.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This new option puts the objects specified by `<filter-spec>` into a
separate packfile.
This could be useful if, for example, some blobs take up a lot of
precious space on fast storage while they are rarely accessed. It could
make sense to move them into a separate cheaper, though slower, storage.
It's possible to find which new packfile contains the filtered out
objects using one of the following:
- `git verify-pack -v ...`,
- `test-tool find-pack ...`, which a previous commit added,
- `--filter-to=<dir>`, which a following commit will add to specify
where the pack containing the filtered out objects will be.
This feature is implemented by running `git pack-objects` twice in a
row. The first command is run with `--filter=<filter-spec>`, using the
specified filter. It packs objects while omitting the objects specified
by the filter. Then another `git pack-objects` command is launched using
`--stdin-packs`. We pass it all the previously existing packs into its
stdin, so that it will pack all the objects in the previously existing
packs. But we also pass into its stdin, the pack created by the previous
`git pack-objects --filter=<filter-spec>` command as well as the kept
packs, all prefixed with '^', so that the objects in these packs will be
omitted from the resulting pack. The result is that only the objects
filtered out by the first `git pack-objects` command are in the pack
resulting from the second `git pack-objects` command.
As the interactions with kept packs are a bit tricky, a few related
tests are added.
Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: John Cai <johncai86@gmail.com>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a new find_pack_prefix() to refactor code that handles finding
the pack prefix from the packtmp and packdir global variables, as we are
going to need this feature again in following commit.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Create a new finish_pack_objects_cmd() to refactor duplicated code
that handles reading the packfile names from the output of a
`git pack-objects` command and putting it into a string_list, as well as
calling finish_command().
While at it, beautify a code comment a bit in the new function.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The code to keep track of existing packs in the repository while
repacking has been refactored.
* tb/repack-existing-packs-cleanup:
builtin/repack.c: extract common cruft pack loop
builtin/repack.c: avoid directly inspecting "util"
builtin/repack.c: store existing cruft packs separately
builtin/repack.c: extract `has_existing_non_kept_packs()`
builtin/repack.c: extract redundant pack cleanup for existing packs
builtin/repack.c: extract redundant pack cleanup for --geometric
builtin/repack.c: extract marking packs for deletion
builtin/repack.c: extract structure to store existing packs
When generating the list of packs to store in a MIDX (when given the
`--write-midx` option), we include any cruft packs both during
--geometric and non-geometric repacks.
But the rules for when we do and don't have to check whether any of
those cruft packs were queued for deletion differ slightly between the
two cases.
But the two can be unified, provided there is a little bit of extra
detail added in the comment to clarify when it is safe to avoid checking
for any pending deletions (and why it is OK to do so even when not
required).
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `->util` field corresponding to each string_list_item is used to
track the existence of some pack at the beginning of a repack operation
was originally intended to be used as a bitfield.
This bitfield tracked:
- (1 << 0): whether or not the pack should be deleted
- (1 << 1): whether or not the pack is cruft
The previous commit removed the use of the second bit, but a future
patch (from a different series than this one) will introduce a new use
of it.
So we could stop treating the util pointer as a bitfield and instead
start treating it as if it were a boolean. But this would require some
backtracking when that later patch is applied.
Instead, let's avoid touching the ->util field directly, and instead
introduce convenience functions like:
- pack_mark_for_deletion()
- pack_is_marked_for_deletion()
Helped-by: Junio C Hamano <gitster@pobox.com>
Helped-by: Jeff King <peff@peff.net>
Helped-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When repacking with the `--write-midx` option, we invoke the function
`midx_included_packs()` in order to produce the list of packs we want to
include in the resulting MIDX.
This list is comprised of:
- existing .keep packs
- any pack(s) which were written earlier in the same process
- any unchanged packs when doing a `--geometric` repack
- any cruft packs
Prior to this patch, we stored pre-existing cruft and non-cruft packs
together (provided those packs are non-kept). This meant we needed an
additional bit to indicate which non-kept pack(s) were cruft versus
those that aren't.
But alternatively we can store cruft packs in a separate list, avoiding
the need for this extra bit, and simplifying the code below.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When there is:
- at least one pre-existing packfile (which is not marked as kept),
- repacking with the `-d` flag, and
- not doing a cruft repack
, then we pass a handful of additional options to the inner
`pack-objects` process, like `--unpack-unreachable`,
`--keep-unreachable`, and `--pack-loose-unreachable`, in addition to
marking any packs we just wrote for promisor remotes as kept in-core
(with `--keep-pack`, as opposed to the presence of a ".keep" file on
disk).
Because we store both cruft and non-cruft packs together in the same
`existing.non_kept_packs` list, it suffices to check its `nr` member to
see if it is zero or not.
But a following change will store cruft- and non-cruft packs separately,
meaning this check would break as a result. Prepare for this by
extracting this part of the check into a new helper function called
`has_existing_non_kept_packs()`.
This patch does not introduce any functional changes, but prepares us to
make a more isolated change in a subsequent patch.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To remove redundant packs at the end of a repacking operation, Git uses
its `remove_redundant_pack()` function in a loop over the set of
pre-existing, non-kept packs.
In a later commit, we will split this list into two, one for
pre-existing cruft pack(s), and another for non-cruft pack(s). Prepare
for this by factoring out the routine to loop over and delete redundant
packs into its own function.
Instead of calling `remove_redundant_pack()` directly, we now will call
`remove_redundant_existing_packs()`, which itself dispatches a call to
`remove_redundant_packs_1()`. Note that the geometric repacking code
will still call `remove_redundant_pack()` directly, but see the previous
commit for more details.
Having `remove_redundant_packs_1()` exist as a separate function may
seem like overkill in this patch. However, a later patch will call
`remove_redundant_packs_1()` once over two separate lists, so this
refactoring sets us up for that.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To reduce the complexity of the already quite-long `cmd_repack()`
implementation, extract out the parts responsible for deleting redundant
packs from a geometric repack out into its own sub-routine.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
At the end of a repack (when given `-d`), Git attempts to remove any
packs which have been made "redundant" as a result of the repacking
operation. For example, an all-into-one (`-A` or `-a`) repack makes
every pre-existing pack which is not marked as kept redundant. Geometric
repacks (with `--geometric=<n>`) make any packs which were rolled up
redundant, and so on.
But before deleting the set of packs we think are redundant, we first
check to see whether or not we just wrote a pack which is identical to
any one of the packs we were going to delete. When this is the case, Git
must avoid deleting that pack, since it matches a pack we just wrote
(so deleting it may cause the repository to become corrupt).
Right now we only process the list of non-kept packs in a single pass.
But a future change will split the existing non-kept packs further into
two lists: one for cruft packs, and another for non-cruft packs.
Factor out this routine to prepare for calling it twice on two separate
lists in a future patch.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The repack machinery needs to keep track of which packfiles were present
in the repository at the beginning of a repack, segmented by whether or
not each pack is marked as kept.
The names of these packs are stored in two `string_list`s, corresponding
to kept- and non-kept packs, respectively. As a consequence, many
functions within the repack code need to take both `string_list`s as
arguments, leading to code like this:
ret = write_cruft_pack(&cruft_po_args, packtmp, pack_prefix,
cruft_expiration, &names,
&existing_nonkept_packs, /* <- */
&existing_kept_packs); /* <- */
Wrap up this pair of `string_list`s into a single structure that stores
both. This saves us from having to pass both string lists separately,
and prepares for adding additional fields to this structure.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When pack-objects learned the `--cruft` option back in b757353676
(builtin/pack-objects.c: --cruft without expiration, 2022-05-20), we
explicitly forbade `--cruft` with `--max-pack-size`.
At the time, there was no specific rationale given in the patch for not
supporting the `--max-pack-size` option with `--cruft`. (As best I can
remember, it's because we were trying to push users towards only ever
having a single cruft pack, but I cannot be sure).
However, `--max-pack-size` is flexible enough that it already works with
`--cruft` and can shard unreachable objects across multiple cruft packs,
creating separate ".mtimes" files as appropriate. In fact, the
`--max-pack-size` option worked with `--cruft` as far back as
b757353676!
This is because we overwrite the `written_list`, and pass down the
appropriate length, i.e. the number of objects written in each pack
shard.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The `pack_geometry` struct is used to maintain and partition a list of
packfiles into a "frozen" set (to be left alone), and a non-frozen set
(to be combined into a single new pack). In the previous commit, we
removed a leak caused by neglecting to free() the heap allocated space
used to store the structure itself.
But there is no need for this structure to live on the heap anyway.
Instead, let's move it to be stack allocated, eliminating the
possibility of a direct leak like the one addressed in the previous
patch.
The one minor hitch is that we use the NULL-ness of the pack_geometry's
struct pointer to determine whether or not we are performing a geometric
repack with `--geometric=<d>`. But since we only initialize the
pack_geometry structure when the `geometric_factor` is non-zero, we can
use that variable (based on whether or not it is equal to zero) to
determine whether or not we are performing a geometric repack.
There are a couple of spots that have access to a pointer to the
pack_geometry struct, but not the geometric_factor itself. Instead of
passing in an additional variable, let's make the geometric_factor a
field of the pack_geometry struct.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the program is ending, we call clear_pack_geometry() to free any
resources in the pack_geometry struct. But the struct itself is
allocated on the heap, and leak-checkers will complain about the
resulting small leak.
This one was marked by Coverity as a "new" leak, though it has existed
since 0fabafd0b9 (builtin/repack.c: add '--geometric' option,
2021-02-22). This might be because recent unrelated changes in the file
confused it about what is new and what is not. But regardless, it is
worth addressing.
We can fix it easily by free-ing the struct. We'll convert our "clear"
function to "free", since the allocation happens in the matching init()
function (though since there is only one call to each, and the struct is
local to this file, it's mostly academic).
Another option would be to put the struct on the stack rather than the
heap. However, this gets tricky, as we check the pointer against NULL in
several places to decide whether we're in geometric mode.
Signed-off-by: Jeff King <peff@peff.net>
Acked-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The recent change to "git repack" made it react less nicely when a
leftover .idx file that no longer has the corresponding .pack file
in the repository, which has been corrected.
* tb/repack-cleanup:
builtin/repack.c: avoid dir traversal in `collect_pack_filenames()`
builtin/repack.c: only repack `.pack`s that exist
Further shuffling of declarations across header files to streamline
file dependencies.
* cw/compat-util-header-cleanup:
git-compat-util: move alloc macros to git-compat-util.h
treewide: remove unnecessary includes for wrapper.h
kwset: move translation table from ctype
sane-ctype.h: create header for sane-ctype macros
git-compat-util: move wrapper.c funcs to its header
git-compat-util: move strbuf.c funcs to its header
When repacking, the function `collect_pack_filenames()` is responsible
for collecting the set of existing packs in the repository, and
partitioning them into "kept" (if the pack has a ".keep" file or was
given via `--keep-pack`) and "nonkept" (otherwise) lists.
This function comes from the original C port of git-repack.sh from back
in a1bbc6c017 (repack: rewrite the shell script in C, 2013-09-15),
where it first appears as `get_non_kept_pack_filenames()`. At the time,
the implementation was a fairly direct translation from the relevant
portion of git-repack.sh, which looped over the results of
find "$PACKDIR" -type f -name '*.pack'
either ignoring the pack as kept, or adding it to the list of existing
packs.
So the choice to directly translate this function in terms of
`readdir()` in a1bbc6c017 made sense. At the time, it was possible to
refine the C version in terms of packed_git structs, but was never done.
However, manually enumerating a repository's packs via `readdir()` is
confusing and error-prone. It leads to frustrating inconsistencies
between which packs Git considers to be part of a repository (i.e.,
could be found in the list of packs from `get_all_packs()`), and which
packs `collect_pack_filenames()` considers to meet the same criteria.
This bit us in 73320e49ad (builtin/repack.c: only collect fully-formed
packs, 2023-06-07), and again in the previous commit.
Prevent these issues from biting us in the future by implementing the
`collect_pack_filenames()` function by looping over an array of pointers
to `packed_git` structs, ensuring that we use the same criteria to
determine the set of available packs.
One gotcha here is that we have to ignore non-local packs, since the
original version of `collect_pack_filenames()` only looks at the local
pack directory to collect existing packs.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In 73320e49ad (builtin/repack.c: only collect fully-formed packs,
2023-06-07), we switched the check for which packs to collect by
starting at the .idx files and looking for matching .pack files. This
avoids trying to repack pack-files that have not had their pack-indexes
installed yet.
However, it does cause maintenance to halt if we find the (problematic,
but not insurmountable) case of a .idx file without a corresponding
.pack file. In an environment where packfile maintenance is a critical
function, such a hard stop is costly and requires human intervention to
resolve (by deleting the .idx file).
This was not the case before. We successfully repacked through this
scenario until the recent change to scan for .idx files.
Further, if we are actually in a case where objects are missing, we
detect this at a different point during the reachability walk.
In other cases, Git prepares its list of packfiles by scanning .idx
files and then only adds it to the packfile list if the corresponding
.pack file exists. It even does so without a warning! (See
add_packed_git() in packfile.c for details.)
This case is much less likely to occur than the failures seen before
73320e49ad. Packfiles are "installed" by writing the .pack file before
the .idx and that process can be interrupted. Packfiles _should_ be
deleted by deleting the .idx first, followed by the .pack file, but
unlink_pack_path() does not do this: it deletes the .pack _first_,
allowing a window where this process could be interrupted. We leave the
consideration of changing this order as a separate concern. Knowing that
this condition is possible from interrupted Git processes and not other
tools lends some weight that Git should be more flexible around this
scenario.
Add a check to see if the .pack file exists before adding it to the list
for repacking. This will stop a number of maintenance failures seen in
production but fixed by deleting the .idx files.
This brings us closer to the case before 73320e49ad in that 'git
repack' will not fail when there is an orphaned .idx file, at least, not
due to the way we scan for packfiles. In the case that the .pack file
was erroneously deleted without copies of its objects in other installed
packfiles, then 'git repack' will fail due to the reachable object walk.
This does resolve the case where automated repacks will no longer be
halted on this case. The tests in t7700 show both these successful
scenarios and the case of failing if the .pack was truly required.
Signed-off-by: Derrick Stolee <derrickstolee@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Reduce reliance on a global state in the config reading API.
* gc/config-context:
config: pass source to config_parser_event_fn_t
config: add kvi.path, use it to evaluate includes
config.c: remove config_reader from configsets
config: pass kvi to die_bad_number()
trace2: plumb config kvi
config.c: pass ctx with CLI config
config: pass ctx with config files
config.c: pass ctx in configsets
config: add ctx arg to config_fn_t
urlmatch.h: use config_fn_t type
config: inline git_color_default_config
alloc_nr, ALLOC_GROW, and ALLOC_GROW_BY are commonly used macros for
dynamic array allocation. Moving these macros to git-compat-util.h with
the other alloc macros focuses alloc.[ch] to allocation for Git objects
and additionally allows us to remove inclusions to alloc.h from files
that solely used the above macros.
Signed-off-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Header files cleanup.
* en/header-split-cache-h-part-3: (28 commits)
fsmonitor-ll.h: split this header out of fsmonitor.h
hash-ll, hashmap: move oidhash() to hash-ll
object-store-ll.h: split this header out of object-store.h
khash: name the structs that khash declares
merge-ll: rename from ll-merge
git-compat-util.h: remove unneccessary include of wildmatch.h
builtin.h: remove unneccessary includes
list-objects-filter-options.h: remove unneccessary include
diff.h: remove unnecessary include of oidset.h
repository: remove unnecessary include of path.h
log-tree: replace include of revision.h with simple forward declaration
cache.h: remove this no-longer-used header
read-cache*.h: move declarations for read-cache.c functions from cache.h
repository.h: move declaration of the_index from cache.h
merge.h: move declarations for merge.c from cache.h
diff.h: move declaration for global in diff.c from cache.h
preload-index.h: move declarations for preload-index.c from elsewhere
sparse-index.h: move declarations for sparse-index.c from cache.h
name-hash.h: move declarations for name-hash.c from cache.h
run-command.h: move declarations for run-command.c from cache.h
...
Add a new "const struct config_context *ctx" arg to config_fn_t to hold
additional information about the config iteration operation.
config_context has a "struct key_value_info kvi" member that holds
metadata about the config source being read (e.g. what kind of config
source it is, the filename, etc). In this series, we're only interested
in .kvi, so we could have just used "struct key_value_info" as an arg,
but config_context makes it possible to add/adjust members in the future
without changing the config_fn_t signature. We could also consider other
ways of organizing the args (e.g. moving the config name and value into
config_context or key_value_info), but in my experiments, the
incremental benefit doesn't justify the added complexity (e.g. a
config_fn_t will sometimes invoke another config_fn_t but with a
different config value).
In subsequent commits, the .kvi member will replace the global "struct
config_reader" in config.c, making config iteration a global-free
operation. It requires much more work for the machinery to provide
meaningful values of .kvi, so for now, merely change the signature and
call sites, pass NULL as a placeholder value, and don't rely on the arg
in any meaningful way.
Most of the changes are performed by
contrib/coccinelle/config_fn_ctx.pending.cocci, which, for every
config_fn_t:
- Modifies the signature to accept "const struct config_context *ctx"
- Passes "ctx" to any inner config_fn_t, if needed
- Adds UNUSED attributes to "ctx", if needed
Most config_fn_t instances are easily identified by seeing if they are
called by the various config functions. Most of the remaining ones are
manually named in the .cocci patch. Manual cleanups are still needed,
but the majority of it is trivial; it's either adjusting config_fn_t
that the .cocci patch didn't catch, or adding forward declarations of
"struct config_context ctx" to make the signatures make sense.
The non-trivial changes are in cases where we are invoking a config_fn_t
outside of config machinery, and we now need to decide what value of
"ctx" to pass. These cases are:
- trace2/tr2_cfg.c:tr2_cfg_set_fl()
This is indirectly called by git_config_set() so that the trace2
machinery can notice the new config values and update its settings
using the tr2 config parsing function, i.e. tr2_cfg_cb().
- builtin/checkout.c:checkout_main()
This calls git_xmerge_config() as a shorthand for parsing a CLI arg.
This might be worth refactoring away in the future, since
git_xmerge_config() can call git_default_config(), which can do much
more than just parsing.
Handle them by creating a KVI_INIT macro that initializes "struct
key_value_info" to a reasonable default, and use that to construct the
"ctx" arg.
Signed-off-by: Glen Choo <chooglen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The vast majority of files including object-store.h did not need dir.h
nor khash.h. Split the header into two files, and let most just depend
upon object-store-ll.h, while letting the two callers that need it
depend on the full object-store.h.
After this patch:
$ git grep -h include..object-store | sort | uniq -c
2 #include "object-store.h"
129 #include "object-store-ll.h"
Diff best viewed with `--color-moved`.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This also made it clear that several .c files that depended upon path.h
were missing a #include for it; add the missing includes while at it.
Signed-off-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
To partition the set of packs based on which ones are "kept" (either
they have a .keep file, or were otherwise marked via the `--keep-pack`
option) and "non-kept" ones (anything else), `git repack` uses its
`collect_pack_filenames()` function.
Ordinarily, we would rely on a convenience function such as
`get_all_packs()` to enumerate and partition the set of packs. But
`collect_pack_filenames()` uses `readdir()` directly to read the
contents of the "$GIT_DIR/objects/pack" directory, and adds each entry
ending in ".pack" to the appropriate list (either kept, or non-kept as
above).
This is subtly racy, since `collect_pack_filenames()` may see a pack
that is not fully staged (i.e., it is missing its ".idx" file).
Ordinarily, this doesn't cause a problem. But it can cause issues when
generating a cruft pack.
This is because `git repack` feeds (among other things) the list of
existing kept packs down to `git pack-objects --cruft` to indicate that
any kept packs will not be removed from the repository (so that the
cruft pack machinery can avoid packing objects that appear in those
packs as cruft).
But `read_cruft_objects()` lists packfiles by calling `get_all_packs()`.
So if a ".pack" file exists (necessary to get that pack to appear to
`collect_pack_filenames()`), but doesn't have a corresponding ".idx"
file (necessary to get that pack to appear via `get_all_packs()`), we'll
complain with:
fatal: could not find pack '.tmp-5841-pack-a6b0150558609c323c496ced21de6f4b66589260.pack'
Fix the above by teaching `collect_pack_filenames()` to only collect
packs with their corresponding `*.idx` files in place, indicating that
those packs have been fully staged.
There are a couple of things worth noting:
- Since each entry in the `extra_keep` list (which contains the
`--keep-pack` names) has a `*.pack` suffix, we'll have to swap the
suffix from ".pack" to ".idx", and compare that instead.
- Since we use the the `fname_kept_list` to figure out which packs to
delete (with `git repack -d`), we would have previously deleted a
`*.pack` with no index (since the existince of a ".pack" file is
necessary and sufficient to include that pack in the list of
existing non-kept packs).
Now we will leave it alone (since that pack won't appear in the
list). This is far more correct behavior, since we don't want
to race with a pack being staged. Deleting a partially staged pack
is unlikely, however, since the window of time between staging a
pack and moving its .idx file into place is miniscule.
Note that this window does *not* include the time it takes to
receive and index the pack, since the incoming data goes into
"$GIT_DIR/objects/tmp_pack_XXXXXX", which does not end in ".pack"
and is thus ignored by collect_pack_filenames().
In the future, this function should probably be rewritten as a callback
to `for_each_file_in_pack_dir()`, but this is the simplest change we
could do in the short-term.
Reported-by: Michael Haggerty <mhagger@github.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
More header clean-up.
* en/header-split-cache-h-part-2: (22 commits)
reftable: ensure git-compat-util.h is the first (indirect) include
diff.h: reduce unnecessary includes
object-store.h: reduce unnecessary includes
commit.h: reduce unnecessary includes
fsmonitor: reduce includes of cache.h
cache.h: remove unnecessary headers
treewide: remove cache.h inclusion due to previous changes
cache,tree: move basic name compare functions from read-cache to tree
cache,tree: move cmp_cache_name_compare from tree.[ch] to read-cache.c
hash-ll.h: split out of hash.h to remove dependency on repository.h
tree-diff.c: move S_DIFFTREE_IFXMIN_NEQ define from cache.h
dir.h: move DTYPE defines from cache.h
versioncmp.h: move declarations for versioncmp.c functions from cache.h
ws.h: move declarations for ws.c functions from cache.h
match-trees.h: move declarations for match-trees.c functions from cache.h
pkt-line.h: move declarations for pkt-line.c functions from cache.h
base85.h: move declarations for base85.c functions from cache.h
copy.h: move declarations for copy.c functions from cache.h
server-info.h: move declarations for server-info.c functions from cache.h
packfile.h: move pack_window and pack_entry from cache.h
...
When "gc" needs to retain unreachable objects, packing them into
cruft packs (instead of exploding them into loose object files) has
been offered as a more efficient option for some time. Now the use
of cruft packs has been made the default and no longer considered
an experimental feature.
* tb/enable-cruft-packs-by-default:
repository.h: drop unused `gc_cruft_packs`
builtin/gc.c: make `gc.cruftPacks` enabled by default
t/t9300-fast-import.sh: prepare for `gc --cruft` by default
t/t6500-gc.sh: add additional test cases
t/t6500-gc.sh: refactor cruft pack tests
t/t6501-freshen-objects.sh: prepare for `gc --cruft` by default
t/t5304-prune.sh: prepare for `gc --cruft` by default
builtin/gc.c: ignore cruft packs with `--keep-largest-pack`
builtin/repack.c: fix incorrect reference to '-C'
pack-write.c: plug a leak in stage_tmp_packfiles()
Geometric repacking ("git repack --geometric=<n>") in a repository
that borrows from an alternate object database had various corner
case bugs, which have been corrected.
* ps/fix-geom-repack-with-alternates:
repack: disable writing bitmaps when doing a local repack
repack: honor `-l` when calculating pack geometry
t/helper: allow chmtime to print verbosely without modifying mtime
pack-objects: extend test coverage of `--stdin-packs` with alternates
pack-objects: fix error when same packfile is included and excluded
pack-objects: fix error when packing same pack twice
pack-objects: split out `--stdin-packs` tests into separate file
repack: fix generating multi-pack-index with only non-local packs
repack: fix trying to use preferred pack in alternates
midx: fix segfault with no packs and invalid preferred pack
When cruft packs were originally being developed, `-C` was designated as
the short-form for `--cruft` (as in `git repack -C`).
This was dropped due to confusion with Git's top-level `-C` option
before submitting to the list. But the reference to it in
`--cruft-expiration`'s help text was never updated. Fix that dangling
reference in this patch.
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
In order to write a bitmap, we need to have full coverage of all objects
that are about to be packed. In the traditional non-multi-pack-index
world this meant we need to do a full repack of all objects into a
single packfile. But in the new multi-pack-index world we can get away
with writing bitmaps when we have multiple packfiles as long as the
multi-pack-index covers all objects.
This is not always the case though. When asked to perform a repack of
local objects, only, then we cannot guarantee to have full coverage of
all objects regardless of whether we do a full repack or a repack with a
multi-pack-index. The end result is that writing the bitmap will fail in
both worlds:
$ git multi-pack-index write --stdin-packs --bitmap <packfiles
warning: Failed to write bitmap index. Packfile doesn't have full closure (object 1529341d78cf45377407369acb0f4ff2b5cdae42 is missing)
error: could not write multi-pack bitmap
Now there are two different ways to fix this. The first one would be to
amend git-multi-pack-index(1) to disable writing bitmaps when we notice
that we don't have full object coverage.
- We don't have enough information in git-multi-pack-index(1) in
order to tell whether the local repository _should_ have full
coverage. Because even when connected to an alternate object
directory, it may be the case that we still have all objects
around in the main object database.
- git-multi-pack-index(1) is quite a low-level tool. Automatically
disabling functionality that it was asked to provide does not feel
like the right thing to do.
We can easily fix it at a higher level in git-repack(1) though. When
asked to only include local objects via `-l` and when connected to an
alternate object directory then we will override the user's ask and
disable writing bitmaps with a warning. This is similar to what we do in
git-pack-objects(1), where we also disable writing bitmaps in case we
omit an object from the pack.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When the user passes `-l` to git-repack(1), then they essentially ask us
to only repack objects part of the local object database while ignoring
any packfiles part of an alternate object database. And we in fact honor
this bit when doing a geometric repack as the resulting packfile will
only ever contain local objects.
What we're missing though is that we don't take locality of packfiles
into account when computing whether the geometric sequence is intact or
not. So even though we would only ever roll up local packfiles anyway,
we could end up trying to repack because of non-local packfiles. This
does not make much sense, and in the worst case it can cause us to try
and do the geometric repack over and over again because we're never able
to restore the geometric sequence.
Fix this bug by honoring whether the user has passed `-l`. If so, we
skip adding any non-local packfiles to the pack geometry.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When writing the multi-pack-index with geometric repacking we will add
all packfiles to the index that are part of the geometric sequence. This
can potentially also include packfiles borrowed from an alternate object
directory. But given that a multi-pack-index can only ever include packs
that are part of the main object database this does not make much sense
whatsoever.
In the edge case where all packfiles are contained in the alternate
object database and the local repository has none itself this bug can
cause us to invoke git-multi-pack-index(1) with only non-local packfiles
that it ultimately cannot find. This causes it to return an error and
thus causes the geometric repack to fail.
Fix the code to skip non-local packfiles.
Co-authored-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
When doing a geometric repack with multi-pack-indices, then we ask
git-multi-pack-index(1) to use the largest packfile as the preferred
pack. It can happen though that the largest packfile is not part of the
main object database, but instead part of an alternate object database.
The result is that git-multi-pack-index(1) will not be able to find the
preferred pack and print a warning. It then falls back to use the first
packfile that the multi-pack-index shall reference.
Fix this bug by only considering packfiles as preferred pack that are
local. This is the right thing to do given that a multi-pack-index
should never reference packfiles borrowed from an alternate.
While at it, rename the function `get_largest_active_packfile()` to
`get_preferred_pack()` to better document its intent.
Helped-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Patrick Steinhardt