| commit | 9fec7b213045135655354e864d15894175428d5a | [log] [tgz] |
|---|---|---|
| author | Patrick Steinhardt <ps@pks.im> | Wed Sep 01 15:09:50 2021 +0200 |
| committer | Junio C Hamano <gitster@pobox.com> | Wed Sep 01 12:43:56 2021 -0700 |
| tree | fd1a8c4829f66efa9a9342c4342a0f4499223a87 | |
| parent | 47c61004c7cfbb8662b13fac813b45e3fd214665 [diff] |
connected: refactor iterator to return next object ID directly
The object ID iterator used by the connectivity checks returns the next
object ID via an out-parameter and then uses a return code to indicate
whether an item was found. This is a bit roundabout: instead of a
separate error code, we can just return the next object ID directly and
use `NULL` pointers as indicator that the iterator got no items left.
Furthermore, this avoids a copy of the object ID.
Refactor the iterator and all its implementations to return object IDs
directly. This brings a tiny performance improvement when doing a mirror-fetch of a repository with about 2.3M refs:
Benchmark #1: 328dc58b49919c43897240f2eabfa30be2ce32a4~: git-fetch
Time (mean ± σ): 30.110 s ± 0.148 s [User: 27.161 s, System: 5.075 s]
Range (min … max): 29.934 s … 30.406 s 10 runs
Benchmark #2: 328dc58b49919c43897240f2eabfa30be2ce32a4: git-fetch
Time (mean ± σ): 29.899 s ± 0.109 s [User: 26.916 s, System: 5.104 s]
Range (min … max): 29.696 s … 29.996 s 10 runs
Summary
'328dc58b49919c43897240f2eabfa30be2ce32a4: git-fetch' ran
1.01 ± 0.01 times faster than '328dc58b49919c43897240f2eabfa30be2ce32a4~: git-fetch'
While this 1% speedup could be labelled as statistically insignificant,
the speedup is consistent on my machine. Furthermore, this is an end to
end test, so it is expected that the improvement in the connectivity
check itself is more significant.
Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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