| commit | 024aa4696c788eb1b07be53331f770605696ffba | [log] [tgz] |
|---|---|---|
| author | Takuto Ikuta <tikuta@chromium.org> | Wed Mar 14 15:32:42 2018 +0900 |
| committer | Junio C Hamano <gitster@pobox.com> | Wed Mar 14 11:17:26 2018 -0700 |
| tree | f9ca00f64a166c76f711b60f77235b0aaf4da9cd | |
| parent | d0db9edba0050ada6f6eac68061599690d2a4333 [diff] |
fetch-pack.c: use oidset to check existence of loose object When fetching from a repository with large number of refs, because to check existence of each refs in local repository to packed and loose objects, 'git fetch' ends up doing a lot of lstat(2) to non-existing loose form, which makes it slow. Instead of making as many lstat(2) calls as the refs the remote side advertised to see if these objects exist in the loose form, first enumerate all the existing loose objects in hashmap beforehand and use it to check existence of them if the number of refs is larger than the number of loose objects. With this patch, the number of lstat(2) calls in `git fetch` is reduced from 411412 to 13794 for chromium repository, it has more than 480000 remote refs. I took time stat of `git fetch` when fetch-pack happens for chromium repository 3 times on linux with SSD. * with this patch 8.105s 8.309s 7.640s avg: 8.018s * master 12.287s 11.175s 12.227s avg: 11.896s On my MacBook Air which has slower lstat(2). * with this patch 14.501s * master 1m16.027s `git fetch` on slow disk will be improved largely. Signed-off-by: Takuto Ikuta <tikuta@chromium.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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