git/walker.c, branch v2.51.2

Merge branch 'rs/pop-recent-commit-with-prio-queue'

2025-07-28T19:02:34Z

The pop_most_recent_commit() function can have quite expensive worst case performance characteristics, which has been optimized by using prio-queue data structure. * rs/pop-recent-commit-with-prio-queue: commit: use prio_queue_replace() in pop_most_recent_commit() prio-queue: add prio_queue_replace() commit: convert pop_most_recent_commit() to prio_queue

commit: convert pop_most_recent_commit() to prio_queue

2025-07-22T14:28:23Z

pop_most_recent_commit() calls commit_list_insert_by_date() for parent commits, which is itself called in a loop. This can lead to quadratic complexity if there are many merges. Replace the commit_list with a prio_queue to ensure logarithmic worst case complexity and convert all three users. Add a performance test that exercises one of them using a pathological history that consists of 50% merges and 50% root commits to demonstrate the speedup: Test v2.50.1 HEAD ---------------------------------------------------------------------- 1501.2: rev-parse ':/65535' 2.48(2.47+0.00) 0.20(0.19+0.00) -91.9% Alas, sane histories don't benefit from the conversion much, and traversing Git's own history takes a 1% performance hit on my machine: $ hyperfine -w3 -L git ./git_2.50.1,./git '{git} rev-parse :/^Initial.revision' Benchmark 1: ./git_2.50.1 rev-parse :/^Initial.revision Time (mean ± σ): 1.071 s ± 0.004 s [User: 1.052 s, System: 0.017 s] Range (min … max): 1.067 s … 1.078 s 10 runs Benchmark 2: ./git rev-parse :/^Initial.revision Time (mean ± σ): 1.079 s ± 0.003 s [User: 1.060 s, System: 0.017 s] Range (min … max): 1.074 s … 1.083 s 10 runs Summary ./git_2.50.1 rev-parse :/^Initial.revision ran 1.01 ± 0.00 times faster than ./git rev-parse :/^Initial.revision Signed-off-by: René Scharfe Signed-off-by: Junio C Hamano

odb: rename `has_object()`

2025-07-01T21:46:38Z

Rename `has_object()` to `odb_has_object()` to match other functions related to the object database and our modern coding guidelines. Introduce a compatibility wrapper so that any in-flight topics will continue to compile. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

object-store: rename files to "odb.{c,h}"

2025-07-01T21:46:34Z

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 Signed-off-by: Junio C Hamano

treewide: convert users of `repo_has_object_file()` to `has_object()`

2025-04-29T17:08:13Z

As the comment of `repo_has_object_file()` and its `_with_flags()` variant tells us, these functions are considered to be deprecated in favor of `has_object()`. There are a couple of slight benefits in favor of the replacement: - The new function has a short-and-sweet name. - More explicit defaults: `has_object()` doesn't fetch missing objects via promisor remotes, and neither does it reload packfiles if an object wasn't found by default. This ensures that it becomes immediately obvious when a simple object existence check may result in expensive actions. Most importantly though, it is confusing that we have two sets of functions that ultimately do the same thing, but with different defaults. Start sunsetting `repo_has_object_file()` and its `_with_flags()` sibling by replacing all callsites with `has_object()`: - `repo_has_object_file(...)` is equivalent to `has_object(..., HAS_OBJECT_RECHECK_PACKED | HAS_OBJECT_FETCH_PROMISOR)`. - `repo_has_object_file_with_flags(..., OBJECT_INFO_QUICK | OBJECT_INFO_SKIP_FETCH_OBJECT)` is equivalent to `has_object(..., 0)`. - `repo_has_object_file_with_flags(..., OBJECT_INFO_SKIP_FETCH_OBJECT)` is equivalent to `has_object(..., HAS_OBJECT_RECHECK_PACKED)`. - `repo_has_object_file_with_flags(..., OBJECT_INFO_QUICK)` is equivalent to `has_object(..., HAS_OBJECT_FETCH_PROMISOR)`. The replacements should be functionally equivalent. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

object-store: merge "object-store-ll.h" and "object-store.h"

2025-04-15T15:24:37Z

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 Signed-off-by: Junio C Hamano

progress: stop using `the_repository`

2024-12-18T18:44:30Z

Stop using `the_repository` in the "progress" subsystem by passing in a repository when initializing `struct progress`. Furthermore, store a pointer to the repository in that struct so that we can pass it to the trace2 API when logging information. 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 Signed-off-by: Junio C Hamano

refs: allow passing flags when setting up a transaction

2024-11-20T22:59:14Z

Allow passing flags when setting up a transaction such that the behaviour of the transaction itself can be altered. This functionality will be used in a subsequent patch. Adapt callers accordingly. Signed-off-by: Patrick Steinhardt Signed-off-by: Junio C Hamano

http-walker: use object_id instead of bare hash

2024-10-25T21:35:46Z

We long ago switched most code to using object_id structs instead of bare "unsigned char *" hashes. This gives us more type safety from the compiler, and generally makes it easier to understand what we expect in each parameter. But the dumb-http code has lagged behind. And indeed, the whole "walker" subsystem interface has the same problem, though http-walker is the only user left. So let's update the walker interface to pass object_id structs (which we already have anyway at all call sites!), and likewise use those within the http-walker methods that it calls. This cleans up the dumb-http code a bit, but will also let us fix a few more commonly used helper functions. Signed-off-by: Jeff King Signed-off-by: Taylor Blau

refs: add referent to each_ref_fn

2024-08-09T15:47:34Z

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 Signed-off-by: Junio C Hamano