Add a macro to mark code sections that only read from the file system,
along with a config option and documentation.
This facilitates implementation of relatively simple file system level
caches without the need to synchronize with the file system.
Enable read-only sections for 'git status' and preload_index.
Signed-off-by: Karsten Blees <blees@dcon.de>
This topic branch teaches `git clean` to respect NTFS junctions and Unix
bind mounts: it will now stop at those boundaries.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Windows' equivalent to "bind mounts", NTFS junction points, can be
unlinked without affecting the mount target. This is clearly what users
expect to happen when they call `git clean -dfx` in a worktree that
contains NTFS junction points: the junction should be removed, and the
target directory of said junction should be left alone (unless it is
inside the worktree).
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
It seems to be not exactly rare on Windows to install NTFS junction
points (the equivalent of "bind mounts" on Linux/Unix) in worktrees,
e.g. to map some development tools into a subdirectory.
In such a scenario, it is pretty horrible if `git clean -dfx` traverses
into the mapped directory and starts to "clean up".
Let's just not do that. Let's make sure before we traverse into a
directory that it is not a mount point (or junction).
This addresses https://github.com/git-for-windows/git/issues/607
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
On Windows, symbolic links actually have a type depending on the target:
it can be a file or a directory.
In certain circumstances, this poses problems, e.g. when a symbolic link
is supposed to point into a submodule that is not checked out, so there
is no way for Git to auto-detect the type.
To help with that, we will add support over the course of the next
commits to specify that symlink type via the Git attributes. This
requires an index_state, though, something that Git for Windows'
`symlink()` replacement cannot know about because the function signature
is defined by the POSIX standard and not ours to change.
So let's introduce a helper function to create symbolic links that
*does* know about the index_state.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
While this command is definitely something we _want_, chances are that
upstreaming this will require substantial changes.
We still want to be able to experiment with this before that, to focus
on what we need out of this command: To assist with diagnosing issues
with large repositories, as well as to help monitoring the growth and
the associated painpoints of such repositories.
To that end, we are about to integrate this command into
`microsoft/git`, to get the tool into the hands of users who need it
most, with the idea to iterate in close collaboration between these
users and the developers familar with Git's internals.
However, we will definitely want to avoid letting anybody have the
impression that this command, its exact inner workings, as well as its
output format, are anywhere close to stable. To make that fact utterly
clear (and thereby protect the freedom to iterate and innovate freely
before upstreaming the command), let's mark its output as experimental
in all-caps, as the first thing we do.
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
The 'git survey' builtin provides several detail tables, such as "top
files by on-disk size". The size of these tables defaults to 10,
currently.
Allow the user to specify this number via a new --top=<N> option or the
new survey.top config key.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Since we are already walking our reachable objects using the path-walk API,
let's now collect lists of the paths that contribute most to different
metrics. Specifically, we care about
* Number of versions.
* Total size on disk.
* Total inflated size (no delta or zlib compression).
This information can be critical to discovering which parts of the
repository are causing the most growth, especially on-disk size. Different
packing strategies might help compress data more efficiently, but the toal
inflated size is a representation of the raw size of all snapshots of those
paths. Even when stored efficiently on disk, that size represents how much
information must be processed to complete a command such as 'git blame'.
The exact disk size seems to be not quite robust enough for testing, as
could be seen by the `linux-musl-meson` job consistently failing, possibly
because of zlib-ng deflates differently: t8100.4(git survey
(default)) was failing with a symptom like this:
TOTAL OBJECT SIZES BY TYPE
===============================================
Object Type | Count | Disk Size | Inflated Size
------------+-------+-----------+--------------
- Commits | 10 | 1523 | 2153
+ Commits | 10 | 1528 | 2153
Trees | 10 | 495 | 1706
Blobs | 10 | 191 | 101
- Tags | 4 | 510 | 528
+ Tags | 4 | 547 | 528
This means: the disk size is unlikely something we can verify robustly.
Since zlib-ng seems to increase the disk size of the tags from 528 to
547, we cannot even assume that the disk size is always smaller than the
inflated size. We will most likely want to either skip verifying the
disk size altogether, or go for some kind of fuzzy matching, say, by
replacing `s/ 1[45][0-9][0-9] / ~1.5k /` and `s/ [45][0-9][0-9] / ~½k /`
or something like that.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
In future changes, we will make use of these methods. The intention is to
keep track of the top contributors according to some metric. We don't want
to store all of the entries and do a sort at the end, so track a
constant-size table and remove rows that get pushed out depending on the
chosen sorting algorithm.
Co-authored-by: Jeff Hostetler <git@jeffhostetler.com>
Signed-off-by; Jeff Hostetler <git@jeffhostetler.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Now that we have explored objects by count, we can expand that a bit more to
summarize the data for the on-disk and inflated size of those objects. This
information is helpful for diagnosing both why disk space (and perhaps
clone or fetch times) is growing but also why certain operations are slow
because the inflated size of the abstract objects that must be processed is
so large.
Note: zlib-ng is slightly more efficient even at those small sizes. Even
between zlib versions, there are slight differences in compression. To
accommodate for that in the tests, not the exact numbers but some rough
approximations are validated (the test should validate `git survey`,
after all, not zlib).
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
At the moment, nothing is obvious about the reason for the use of the
path-walk API, but this will become more prevelant in future iterations. For
now, use the path-walk API to sum up the counts of each kind of object.
For example, this is the reachable object summary output for my local repo:
REACHABLE OBJECT SUMMARY
========================
Object Type | Count
------------+-------
Tags | 1343
Commits | 179344
Trees | 314350
Blobs | 184030
Signed-off-by: Derrick Stolee <stolee@gmail.com>
When 'git survey' provides information to the user, this will be presented
in one of two formats: plaintext and JSON. The JSON implementation will be
delayed until the functionality is complete for the plaintext format.
The most important parts of the plaintext format are headers specifying the
different sections of the report and tables providing concreted data.
Create a custom table data structure that allows specifying a list of
strings for the row values. When printing the table, check each column for
the maximum width so we can create a table of the correct size from the
start.
The table structure is designed to be flexible to the different kinds of
output that will be implemented in future changes.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
By default we will scan all references in "refs/heads/", "refs/tags/"
and "refs/remotes/".
Add command line opts let the use ask for all refs or a subset of them
and to include a detached HEAD.
Signed-off-by: Jeff Hostetler <git@jeffhostetler.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Start work on a new 'git survey' command to scan the repository
for monorepo performance and scaling problems. The goal is to
measure the various known "dimensions of scale" and serve as a
foundation for adding additional measurements as we learn more
about Git monorepo scaling problems.
The initial goal is to complement the scanning and analysis performed
by the GO-based 'git-sizer' (https://github.com/github/git-sizer) tool.
It is hoped that by creating a builtin command, we may be able to take
advantage of internal Git data structures and code that is not
accessible from GO to gain further insight into potential scaling
problems.
Co-authored-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Jeff Hostetler <git@jeffhostetler.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
The loose object source has been refactored into a proper `struct
odb_source`.
* ps/odb-source-loose:
odb/source-loose: drop pointer to the "files" source
odb/source-loose: stub out remaining callbacks
odb/source-loose: wire up `write_object_stream()` callback
object-file: refactor writing objects to use loose source
odb/source-loose: wire up `write_object()` callback
loose: refactor object map to operate on `struct odb_source_loose`
odb/source-loose: wire up `freshen_object()` callback
odb/source-loose: drop `odb_source_loose_has_object()`
odb/source-loose: wire up `count_objects()` callback
odb/source-loose: wire up `find_abbrev_len()` callback
odb/source-loose: wire up `for_each_object()` callback
odb/source-loose: wire up `read_object_stream()` callback
odb/source-loose: wire up `read_object_info()` callback
odb/source-loose: wire up `close()` callback
odb/source-loose: wire up `reprepare()` callback
odb/source-loose: start converting to a proper `struct odb_source`
odb/source-loose: store pointer to "files" instead of generic source
odb/source-loose: move loose source into "odb/" subsystem
Formatting object name in full hexadecimal form has been optimized
by using a new strbuf_add_oid_hex() helper function.
* rs/strbuf-add-oid-hex:
hex: add and use strbuf_add_oid_hex()
Adding a decimal integer with strbuf_addf("%u") appears commonly;
they have been optimized by using a custom formatter.
* rs/strbuf-add-uint:
ls-tree: use strbuf_add_uint()
ls-files: use strbuf_add_uint()
cat-file: use strbuf_add_uint()
strbuf: add strbuf_add_uint()
"git push" learned to take a "remote group" name to push to, which
causes pushes to multiple places, just like "git fetch" would do.
* ua/push-remote-group:
push: support pushing to a remote group
remote: move remote group resolution to remote.c
remote: fix sign-compare warnings in push_cas_option
"git stash -p" has been optimized by reusing cached index
entries in its temporary index, avoiding unnecessary lstat()
calls on unchanged files.
* aj/stash-patch-optimize-temporary-index:
stash: reuse cached index entries in --patch temporary index
'git restore --staged' has been optimized to avoid unnecessarily expanding
the sparse index when operating on paths within the sparse checkout
definition, by handling sparse directory entries at the tree level.
* ds/restore-sparse-index:
restore: avoid sparse index expansion
t1092: test 'git restore' with sparse index
The GIT_WORK_TREE variable prepared to invoke the push-to-checkout
hook was leaking into the environment even when there was no hook
used and broke the default push-to-deploy (i.e., let "git checkout"
update the working tree only when the working tree is clean).
* ar/receive-pack-worktree-env:
receive-pack: fix updateInstead with core.worktree
The "git pack-objects --path-walk" traversal has been integrated
with several object filters, including blobless and sparse filters.
* ds/path-walk-filters:
path-walk: support `combine` filter
path-walk: support `object:type` filter
path-walk: support `tree:0` filter
t6601: tag otherwise-unreachable trees
pack-objects: support sparse:oid filter with path-walk
path-walk: add pl_sparse_trees to control tree pruning
path-walk: support blob size limit filter
backfill: die on incompatible filter options
path-walk: support blobless filter
path-walk: always emit directly-requested objects
t/perf: add pack-objects filter and path-walk benchmark
pack-objects: pass --objects with --path-walk
t5620: make test work with path-walk var
The "name" argument in git_connect() and related functions has been
converted to a "service" enum to improve type safety and clarify its
purpose.
* jk/connect-service-enum:
transport-helper: fix typo in BUG() message
connect: use "service" enum for "name" argument
The function `odb_source_loose_has_object()` checks whether a specific
object exists as a loose object on disk by using lstat(3p). This
interface is somewhat redundant, as we typically check for object
existence in a generic way via `odb_source_read_object_info()`.
In fact, these two calls are redundant in case the latter is called in a
specific way: when called without an object info request and without the
`OBJECT_INFO_QUICK` flag, then we will end up doing the same call to
lstat(3p) in `read_object_info_from_path()`.
Drop the function and adapt callers to instead use the generic
interface so that its calling conventions align with that of other
sources.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_count_objects()` and its associated helpers from
"object-file.c" into "odb/source-loose.c" and wire it up as the
`count_objects()` callback of the loose source.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Move `odb_source_loose_for_each_object()` and its associated helpers
from "object-file.c" into "odb/source-loose.c" and wire it up as the
`for_each_object()` callback of the loose source.
Again, as in the preceding commit, we are forced to expose a couple of
functions from "object-file.c" that are now used by both subsystems.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
"git cat-file --batch" learns an in-line command "mailmap"
that lets the user toggle use of mailmap.
* sa/cat-file-batch-mailmap-switch:
cat-file: add mailmap subcommand to --batch-command
The fsmonitor daemon has been implemented for Linux.
* pt/fsmonitor-linux:
fsmonitor: convert shown khash to strset in do_handle_client
fsmonitor: add tests for Linux
fsmonitor: add timeout to daemon stop command
fsmonitor: close inherited file descriptors and detach in daemon
run-command: add close_fd_above_stderr option
fsmonitor: implement filesystem change listener for Linux
fsmonitor: rename fsm-settings-darwin.c to fsm-settings-unix.c
fsmonitor: rename fsm-ipc-darwin.c to fsm-ipc-unix.c
fsmonitor: use pthread_cond_timedwait for cookie wait
compat/win32: add pthread_cond_timedwait
fsmonitor: fix hashmap memory leak in fsmonitor_run_daemon
fsmonitor: fix khash memory leak in do_handle_client
t9210, t9211: disable GIT_TEST_SPLIT_INDEX for scalar clone tests
"git bisect" now uses the selected terms (e.g., old/new) more
consistently in its output.
* jr/bisect-custom-terms-in-output:
rev-parse: use selected alternate terms to look up refs
bisect: print bisect terms in single quotes
bisect: use selected alternate terms in status output
Replace `free_commit_list` with `commit_list_free`. The former was
deprecated in 9f18d089 (commit: rename `free_commit_list()` to conform
to coding guidelines, 2026-01-15).
This allows us to remove all the deprecated functions in the
next commit:
• `copy_commit_list`
• `reverse_commit_list`
• `free_commit_list`
Acked-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Kristoffer Haugsbakk <code@khaugsbakk.name>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Many uses of the_repository has been updated to use a more
appropriate struct repository instance in setup.c codepath.
* ps/setup-wo-the-repository:
setup: stop using `the_repository` in `init_db()`
setup: stop using `the_repository` in `create_reference_database()`
setup: stop using `the_repository` in `initialize_repository_version()`
setup: stop using `the_repository` in `check_repository_format()`
setup: stop using `the_repository` in `upgrade_repository_format()`
setup: stop using `the_repository` in `setup_git_directory()`
setup: stop using `the_repository` in `setup_git_directory_gently()`
setup: stop using `the_repository` in `setup_git_env()`
setup: stop using `the_repository` in `set_git_work_tree()`
setup: stop using `the_repository` in `setup_work_tree()`
setup: stop using `the_repository` in `enter_repo()`
setup: stop using `the_repository` in `verify_non_filename()`
setup: stop using `the_repository` in `verify_filename()`
setup: stop using `the_repository` in `path_inside_repo()`
setup: stop using `the_repository` in `prefix_path()`
setup: stop using `the_repository` in `is_inside_work_tree()`
setup: stop using `the_repository` in `is_inside_git_dir()`
setup: replace use of `the_repository` in static functions
The repacking code has been refactored and compaction of MIDX layers
have been implemented, and incremental strategy that does not require
all-into-one repacking has been introduced.
* tb/incremental-midx-part-3.3:
repack: allow `--write-midx=incremental` without `--geometric`
repack: introduce `--write-midx=incremental`
repack: implement incremental MIDX repacking
packfile: ensure `close_pack_revindex()` frees in-memory revindex
builtin/repack.c: convert `--write-midx` to an `OPT_CALLBACK`
repack-geometry: prepare for incremental MIDX repacking
repack-midx: extract `repack_fill_midx_stdin_packs()`
repack-midx: factor out `repack_prepare_midx_command()`
midx: expose `midx_layer_contains_pack()`
repack: track the ODB source via existing_packs
midx: support custom `--base` for incremental MIDX writes
midx: introduce `--no-write-chain-file` for incremental MIDX writes
midx: use `strvec` for `keep_hashes`
midx: build `keep_hashes` array in order
midx: use `strset` for retained MIDX files
midx-write: handle noop writes when converting incremental chains
The negotiation tip options in "git fetch" have been reworked to
allow requiring certain refs to be sent as "have" lines, and to
restrict negotiation to a specific set of refs.
* ds/fetch-negotiation-options:
send-pack: pass negotiation config in push
remote: add remote.*.negotiationInclude config
fetch: add --negotiation-include option for negotiation
negotiator: add have_sent() interface
remote: add remote.*.negotiationRestrict config
transport: rename negotiation_tips
fetch: add --negotiation-restrict option
t5516: fix test order flakiness
The logic to determine that branches in an octopus merge are
independent has been optimized.
* kk/merge-octopus-optim:
merge: use repo_in_merge_bases for octopus up-to-date check
In a lazy clone, "git cherry" and "git grep" often fetch necessary
blob objects one by one from promisor remotes. It has been corrected
to collect necessary object names and fetch them in bulk to gain
reasonable performance.
* en/batch-prefetch:
grep: prefetch necessary blobs
builtin/log: prefetch necessary blobs for `git cherry`
patch-ids.h: add missing trailing parenthesis in documentation comment
promisor-remote: document caller filtering contract
Teach update_some() to handle sparse directory entries at the tree
level rather than expanding the entire sparse index. When iterating a
source tree during checkout/restore operations:
- If a directory matches a sparse directory entry with the same OID,
skip it entirely (no change needed).
- If the OID differs and we are in non-overlay mode (e.g., restore
--staged), update the sparse directory entry's OID in place. This
is semantically correct because non-overlay mode removes paths not
in the source tree anyway.
- In overlay mode (e.g., checkout <tree> -- .), fall through to
recursive descent so individual file entries are preserved
correctly.
Also switch from index_name_pos() to index_name_pos_sparse() for
individual file lookups to avoid triggering ensure_full_index() when
the file is already individually tracked in the index.
Update the test expectation in t1092 to assert that 'restore --staged'
no longer expands the sparse index.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Before a8cc594333 (hooks: fix an obscure TOCTOU "did we just run a
hook?" race, 2022-03-07), when receive.denyCurrentBranch is set to
updateInstead, only one of push_to_checkout() or push_to_deploy()
was called. That commit changed to always call push_to_checkout(),
and then to call push_to_deploy() if push_to_checkout() didn't run
anything.
This change didn't take into account that push_to_checkout() had a
side effect of modifying env, and that modified env broke updating
the worktree in push_to_deploy() if core.worktree was configured.
To fix this, only mutate the environment used inside
push_to_commit(), rather than the environment that might later be
passed to push_to_deploy().
Signed-off-by: Alyssa Ross <hi@alyssa.is>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
`git stash -p` prepares the interactive selection by creating a
temporary index at HEAD, switching `GIT_INDEX_FILE` to it, and then
running the `add -p` machinery.
That temporary index was created by running `git read-tree HEAD`. The
resulting index had no useful cached stat data or fsmonitor-valid bits
from the real index. When `run_add_p()` refreshed that temporary index
before showing the first prompt, it could end up lstat(2)-ing every
tracked file, even in a repository where `git diff` and `git restore -p`
can use fsmonitor to avoid that work.
Create the temporary index in-process instead. Use `unpack_trees()` to
reset the real index contents to HEAD while writing the result to the
temporary index path. For paths whose index entries already match HEAD,
`oneway_merge()` reuses the existing cache entries, preserving their
cached stat data and `CE_FSMONITOR_VALID` state.
This makes the refresh performed by `run_add_p()` behave like the one
used by `git restore -p`: unchanged paths can be skipped via fsmonitor
instead of being scanned again.
In a 206k file repository with `core.fsmonitor` enabled and a one-line
change in one file, time to first prompt dropped from 34.774 seconds to
0.659 seconds. The new perf test file demonstrates similar improvements,
with maen times for without- and with-fsmonitor cases dropping from 6.90
and 6.83 seconds to 0.55 and 0.28 seconds, respectively.
Signed-off-by: Adam Johnson <me@adamj.eu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The --filter=sparse:<oid> option to 'git pack-objects' allows focusing
an object set to a sparse-checkout definition. This reduces the set of
matching blobs while retaining all reachable trees. No server currently
supports fetching with this filter because it is expensive to compute
and reachability bitmaps do not help without a significant effort to
extend the bitmap feature to store bitmaps for each supported sparse-
checkout definition.
Without focusing on serving fetches and clones with these filters, there
are still benefits that could be realized by making this faster. With
the sparse index, it's more realistic now than ever to be able to
operate a local clone that was bootstrapped by a packfile created with
a sparse filter, because the missing trees are not needed to move a
sparse-checkout from one commit to another or to view the history of any
path in scope. Such clones could perhaps be bootstrapped by partial
bundles.
Previously, constructing these sparse packs has been incredibly
computationally inefficient. The revision walk that explores which
objects are in scope spends a lot of time checking each object to see if
it matches the sparse-checkout patterns, causing quadratic behavior
(number of objects times number of sparse-checkout patterns). This
improves somewhat when using cone-mode sparse-checkout patterns that can
use hashtables and prefix matches to determine containment. However, the
check per object is still too expensive for most cases.
This is where the path-walk feature comes in. We can proceed as normal
by placing objects in bins by path and _then_ check a group of objects
all at once. Since sparse:<oid> only restricts blobs, the path-walk must
include all reachable trees while using the cone-mode patterns to skip
blobs at paths outside the sparse scope. This establishes a baseline for
a potential future "treesparse:<oid>" filter that would also restrict
trees, but introducing such a new filter is deferred to a later change.
The implementation here is focused around loading the sparse-checkout
patterns from the provided object ID and checking that the patterns are
indeed cone-mode patterns. We can then load the correct pattern list
into the path walk context and use the logic that already exists from
bff4555767 (backfill: add --sparse option, 2025-02-03), though that
feature loads sparse-checkout patterns from the worktree's local
settings and also restricts tree objects. We use a combination of errors
and warnings to signal problems during this load. The difference is that
errors are likely fatal for the non-path-walk version while the warnings
are probably just implementation details for the path-walk version and
the 'git pack-objects' command can fall back to the revision walk
version.
Now that the SEEN flag is deferred until after pattern checks (from the
previous commit), handle the case where a tree with a shared OID appears
at both an out-of-cone and in-cone path. When trees are not being pruned
(pl_sparse_trees == 0), the path-walk re-walks the tree at the in-cone
path so that in-cone blobs within it are discovered. The new tests in
t5317 and t6601 demonstrate this behavior and would fail without these
changes.
The performance test p5315 shows the impact of this change when using
sparse filters:
Test HEAD~1 HEAD
----------------------------------------------------------------------
5315.10: repack (sparse:oid) 77.98 77.47 -0.7%
5315.11: repack size (sparse:oid) 187.5M 187.4M -0.0%
5315.12: repack (sparse:oid, --path-walk) 77.91 31.41 -59.7%
5315.13: repack size (sparse:oid, --path-walk) 187.5M 161.1M -14.1%
These performance tests were run on the Git repository. The --path-walk
feature shows meaningful space savings (14% smaller for sparse packs)
and dramatic time savings (60% faster) by leveraging the path-walk's
ability to skip blobs outside the sparse scope.
Co-authored-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Taylor Blaue <me@ttaylorr.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The path-walk API prunes trees and blobs when a sparse-checkout pattern
list is provided, which is the correct behavior for 'git backfill
--sparse' since it only needs to fill in objects at paths within the
sparse cone.
However, a future change will use the path-walk API with a sparse:<oid>
filter that restricts only blobs while retaining all reachable trees.
To support both behaviors, add a 'pl_sparse_trees' flag to
path_walk_info. When set (as in 'git backfill --sparse' and the
--stdin-pl test helper mode), the sparse patterns prune both trees and
blobs. When unset, only blobs are filtered and all trees are walked and
reported.
Additionally, move the SEEN flag assignment in add_tree_entries() to
after the sparse pattern and pathspec checks. Previously, SEEN was set
immediately upon discovering an object, before checking whether its path
matched the sparse patterns. When the same object ID appeared at
multiple paths (e.g. sibling directories with identical contents), the
first path to be visited would mark the object as SEEN. If that path was
outside the sparse cone, the object would be skipped there but also
never discovered at its in-cone path.
By deferring the SEEN flag until after the checks pass, objects that are
skipped due to sparse filtering remain discoverable at other paths where
they may be in scope.
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Extend the path-walk API to handle the 'blob:limit=<size>' object
filter natively. This filter omits blobs whose size is equal to or
greater than the given limit, matching the semantics used by the
list-objects-filter machinery.
When revs->filter.choice is LOFC_BLOB_LIMIT, the prepare_filters()
method stores the limit value in info->blob_limit and clears the filter
from revs. If the limit is zero, this degenerates to blob:none (all
blobs excluded), so info->blobs is set to 0 instead.
During walk_path(), blob batches are filtered before being delivered to
the callback: each blob's size is checked via odb_read_object_info(),
and only blobs strictly smaller than the limit are included. Blobs whose
size cannot be determined (e.g. missing in a partial clone) are
conservatively included, matching the existing filter behavior. Empty
batches after filtering are skipped entirely.
The check for inclusion in the path batch looks a little strange at
first glance. We use odb_read_object_info() to read the object's size.
Based on all of the assumptions to this point, this _should_ return
OBJ_BLOB. Since we are focused on the size filter, we use a
short-circuited OR (||) to skip the size check if that method returns a
different object type.
Notice that this inspection of object sizes requires the content to be
present in the repository. The odb_read_object_info() call will download
a missing blob on-demand. This means that the use of the path-walk API
within 'git backfill' would not operate nicely with this filter type.
The intention of that command is to download missing blobs in batches.
Downloading objects one-by-one would go against the point. Update the
validation in 'git backfill' to add its own compatibility check on top
of path_walk_filter_compatible().
Add tests for blob:limit=0 (equivalent to blob:none) and blob:limit=3
(which exercises partial filtering within a batch where some blobs are
kept and others are excluded).
Co-authored-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'git backfill' command uses the path-walk API in a critical way: it
uses the objects output from the command to find the batches of missing
objects that should be requested from the server. Unlike 'git
pack-objects', we cannot fall back to another mechanism.
The previous change added the path_walk_filter_compatible() method that
we can reuse here. Use it during argument validation in cmd_backfill().
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The 'git pack-objects' command can opt-in to using the path-walk API for
scanning the objects. Currently, this option is dynamically disabled if
combined with '--filter=<X>', even when using a simple filter such as
'blob:none' to signal a blobless packfile. This is a common scenario for
repos at scale, so is worth integrating.
Also, users can opt-in to the '--path-walk' option by default through
the pack.usePathWalk=true config option. When using that in a blobless
partial clone, the following warning can appear even though the user did
not specify either option directly:
warning: cannot use --filter with --path-walk
Teach the path-walk API to handle the 'blob:none' object filter
natively. When revs->filter.choice is LOFC_BLOB_NONE, the path-walk
sets info->blobs to 0 (skipping all blob objects) and clears the
filter from revs so that prepare_revision_walk() does not reject the
configuration.
This check is implemented in the static prepare_filters() method, which
will simultaneously check if the input filters are compatible and will
make the appropriate mutations to the path_walk_info and filters if the
path_walk_info is non-NULL. This allows us to use this logic both in the
API method path_walk_filter_compatible() for use in
builtin/pack-objects.c and as a prep step in walk_objects_by_path().
Update the test helper (test-path-walk) to accept --filter=<spec>
as a test-tool option (before '--'), applying it to revs after
setup_revisions() to avoid the --objects requirement check. We can also
revert recent GIT_TEST_PACK_PATH_WALK overrides in t5620.
Also switch test-path-walk from REV_INFO_INIT with manual repo
assignment to repo_init_revisions(), which properly initializes
the filter_spec strbuf needed for filter parsing.
Add tests for blob:none with --all and with a single branch.
The performance test p5315 shows the impact of this change when using
blobless filters:
Test HEAD~1 HEAD
---------------------------------------------------------------------
5315.6: repack (blob:none) 13.53 13.87 +2.5%
5315.7: repack size (blob:none) 137.7M 137.8M +0.1%
5315.8: repack (blob:none, --path-walk) 13.51 23.43 +73.4%
5315.9: repack size (blob:none, --path-walk) 137.7M 115.2M -16.3%
These performance tests were run on the Git repository. The --path-walk
feature shows meaningful space savings (16% smaller for blobless packs)
at the cost of increased computation time due to the two compression
passes. This data demonstrates that the feature is engaged and provides
real compression benefits when --no-reuse-delta forces fresh deltas.
Co-Authored-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Derrick Stolee <stolee@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
