diff options
author | Vincent Ambo <mail@tazj.in> | 2020-11-21T18·20+0100 |
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committer | Vincent Ambo <mail@tazj.in> | 2020-11-21T18·45+0100 |
commit | f4609b896fac842433bd495c166d5987852a6a73 (patch) | |
tree | 95511c465c54c4f5d27e5d39ce187e2a1dd82bd3 /third_party/git/Documentation/technical/commit-graph.txt | |
parent | 082c006c04343a78d87b6c6ab3608c25d6213c3f (diff) |
merge(3p/git): Merge git subtree at v2.29.2 r/1890
This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because there is some breakage in the git build related to the netrc credentials helper which someone has taken care of in nixpkgs. The stable channel is not used for anything other than git, so this should be fine. Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb
Diffstat (limited to 'third_party/git/Documentation/technical/commit-graph.txt')
-rw-r--r-- | third_party/git/Documentation/technical/commit-graph.txt | 28 |
1 files changed, 14 insertions, 14 deletions
diff --git a/third_party/git/Documentation/technical/commit-graph.txt b/third_party/git/Documentation/technical/commit-graph.txt index 729fbcb32f87..f14a7659aa87 100644 --- a/third_party/git/Documentation/technical/commit-graph.txt +++ b/third_party/git/Documentation/technical/commit-graph.txt @@ -22,11 +22,11 @@ as "commit-graph" either in the .git/objects/info directory or in the info directory of an alternate. The commit-graph file stores the commit graph structure along with some -extra metadata to speed up graph walks. By listing commit OIDs in lexi- -cographic order, we can identify an integer position for each commit and -refer to the parents of a commit using those integer positions. We use -binary search to find initial commits and then use the integer positions -for fast lookups during the walk. +extra metadata to speed up graph walks. By listing commit OIDs in +lexicographic order, we can identify an integer position for each commit +and refer to the parents of a commit using those integer positions. We +use binary search to find initial commits and then use the integer +positions for fast lookups during the walk. A consumer may load the following info for a commit from the graph: @@ -85,7 +85,7 @@ have generation number represented by the macro GENERATION_NUMBER_ZERO = 0. Since the commit-graph file is closed under reachability, we can guarantee the following weaker condition on all commits: - If A and B are commits with generation numbers N amd M, respectively, + If A and B are commits with generation numbers N and M, respectively, and N < M, then A cannot reach B. Note how the strict inequality differs from the inequality when we have @@ -210,12 +210,12 @@ file. +---------------------+ | | +-----------------------+ +---------------------+ - | graph-{hash2} |->| | + | graph-{hash2} |->| | +-----------------------+ +---------------------+ | | | +-----------------------+ +---------------------+ | | | | - | graph-{hash1} |->| | + | graph-{hash1} |->| | | | | | +-----------------------+ +---------------------+ | tmp_graphXXX @@ -223,7 +223,7 @@ file. | | | | | | - | graph-{hash0} | + | graph-{hash0} | | | | | | | @@ -323,14 +323,14 @@ Related Links [0] https://bugs.chromium.org/p/git/issues/detail?id=8 Chromium work item for: Serialized Commit Graph -[1] https://public-inbox.org/git/20110713070517.GC18566@sigill.intra.peff.net/ +[1] https://lore.kernel.org/git/20110713070517.GC18566@sigill.intra.peff.net/ An abandoned patch that introduced generation numbers. -[2] https://public-inbox.org/git/20170908033403.q7e6dj7benasrjes@sigill.intra.peff.net/ +[2] https://lore.kernel.org/git/20170908033403.q7e6dj7benasrjes@sigill.intra.peff.net/ Discussion about generation numbers on commits and how they interact with fsck. -[3] https://public-inbox.org/git/20170908034739.4op3w4f2ma5s65ku@sigill.intra.peff.net/ +[3] https://lore.kernel.org/git/20170908034739.4op3w4f2ma5s65ku@sigill.intra.peff.net/ More discussion about generation numbers and not storing them inside commit objects. A valuable quote: @@ -342,9 +342,9 @@ Related Links commit objects (i.e., packv4 or something like the "metapacks" I proposed a few years ago)." -[4] https://public-inbox.org/git/20180108154822.54829-1-git@jeffhostetler.com/T/#u +[4] https://lore.kernel.org/git/20180108154822.54829-1-git@jeffhostetler.com/T/#u A patch to remove the ahead-behind calculation from 'status'. -[5] https://public-inbox.org/git/f27db281-abad-5043-6d71-cbb083b1c877@gmail.com/ +[5] https://lore.kernel.org/git/f27db281-abad-5043-6d71-cbb083b1c877@gmail.com/ A discussion of a "two-dimensional graph position" that can allow reading multiple commit-graph chains at the same time. |