Thread (49 messages) 49 messages, 5 authors, 2021-08-09
STALE1806d
Revisions (3)
  1. v3 current
  2. v4 [diff vs current]
  3. v5 [diff vs current]

[PATCH v3 2/4] revision: stop retrieving reference twice

From: Patrick Steinhardt <hidden>
Date: 2021-08-02 09:38:17
Subsystem: the rest · Maintainer: Linus Torvalds

When queueing up references for the revision walk, `handle_one_ref()`
will resolve the reference's object ID and then queue the ID as pending
object via `add_pending_oid()`. But `add_pending_oid()` will again try
to resolve the object ID to an object, effectively duplicating the work
its caller already did before.

Fix the issue by instead calling `add_pending_object()`, which takes the
already-resolved object as input. In a repository with lots of refs,
this translates in a nearly 10% speedup:

    Benchmark #1: HEAD~: rev-list --unsorted-input --objects --quiet --not --all --not $newrev
      Time (mean ± σ):      5.015 s ±  0.038 s    [User: 4.698 s, System: 0.316 s]
      Range (min … max):    4.970 s …  5.089 s    10 runs

    Benchmark #2: HEAD: rev-list --unsorted-input --objects --quiet --not --all --not $newrev
      Time (mean ± σ):      4.606 s ±  0.029 s    [User: 4.260 s, System: 0.345 s]
      Range (min … max):    4.565 s …  4.657 s    10 runs

    Summary
      'HEAD: rev-list --unsorted-input --objects --quiet --not --all --not $newrev' ran
        1.09 ± 0.01 times faster than 'HEAD~: rev-list --unsorted-input --objects --quiet --not --all --not $newrev'

Signed-off-by: Patrick Steinhardt <redacted>
---
 revision.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/revision.c b/revision.c
index 7eb09009ba..f06a5d63a3 100644
--- a/revision.c
+++ b/revision.c
@@ -1534,7 +1534,7 @@ static int handle_one_ref(const char *path, const struct object_id *oid,
 
 	object = get_reference(cb->all_revs, path, oid, cb->all_flags);
 	add_rev_cmdline(cb->all_revs, object, path, REV_CMD_REF, cb->all_flags);
-	add_pending_oid(cb->all_revs, path, oid, cb->all_flags);
+	add_pending_object(cb->all_revs, object, path);
 	return 0;
 }
 
-- 
2.32.0

Attachments

Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help