From 4f027355f6b6b5b2ba69e23ff50cb7313d13dd70 Mon Sep 17 00:00:00 2001 From: Taylor Blau Date: Mon, 13 Apr 2020 22:04:08 -0600 Subject: builtin/commit-graph.c: support for '--split[=]' With '--split', the commit-graph machinery writes new commits in another incremental commit-graph which is part of the existing chain, and optionally decides to condense the chain into a single commit-graph. This is done to ensure that the asymptotic behavior of looking up a commit in an incremental chain is not dominated by the number of incrementals in that chain. It can be controlled by the '--max-commits' and '--size-multiple' options. In the next two commits, we will introduce additional splitting strategies that can exert additional control over: - when a split commit-graph is and isn't written, and - when the existing commit-graph chain is discarded completely and replaced with another graph To prepare for this, make '--split' take an optional strategy (as in '--split[=]'), and add a new enum to describe which strategy is being used. For now, no strategies are given, and the only enumerated value is 'COMMIT_GRAPH_SPLIT_UNSPECIFIED', indicating the absence of a strategy. Signed-off-by: Taylor Blau Signed-off-by: Junio C Hamano --- Documentation/git-commit-graph.txt | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'Documentation/git-commit-graph.txt') diff --git a/Documentation/git-commit-graph.txt b/Documentation/git-commit-graph.txt index 28d1fee505..10d757c5cc 100644 --- a/Documentation/git-commit-graph.txt +++ b/Documentation/git-commit-graph.txt @@ -57,11 +57,12 @@ or `--stdin-packs`.) With the `--append` option, include all commits that are present in the existing commit-graph file. + -With the `--split` option, write the commit-graph as a chain of multiple -commit-graph files stored in `/info/commit-graphs`. The new commits -not already in the commit-graph are added in a new "tip" file. This file -is merged with the existing file if the following merge conditions are -met: +With the `--split[=]` option, write the commit-graph as a +chain of multiple commit-graph files stored in +`/info/commit-graphs`. Commit-graph layers are merged based on the +strategy and other splitting options. The new commits not already in the +commit-graph are added in a new "tip" file. This file is merged with the +existing file if the following merge conditions are met: + * If `--size-multiple=` is not specified, let `X` equal 2. If the new tip file would have `N` commits and the previous tip has `M` commits and -- cgit v1.3