diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/config/commitgraph.txt | 29 | ||||
| -rw-r--r-- | Documentation/gitformat-commit-graph.txt | 9 |
2 files changed, 32 insertions, 6 deletions
diff --git a/Documentation/config/commitgraph.txt b/Documentation/config/commitgraph.txt index 30604e4a4c..7f8c9d6638 100644 --- a/Documentation/config/commitgraph.txt +++ b/Documentation/config/commitgraph.txt @@ -9,6 +9,29 @@ commitGraph.maxNewFilters:: commit-graph write` (c.f., linkgit:git-commit-graph[1]). commitGraph.readChangedPaths:: - If true, then git will use the changed-path Bloom filters in the - commit-graph file (if it exists, and they are present). Defaults to - true. See linkgit:git-commit-graph[1] for more information. + Deprecated. Equivalent to commitGraph.changedPathsVersion=-1 if true, and + commitGraph.changedPathsVersion=0 if false. (If commitGraph.changedPathVersion + is also set, commitGraph.changedPathsVersion takes precedence.) + +commitGraph.changedPathsVersion:: + Specifies the version of the changed-path Bloom filters that Git will read and + write. May be -1, 0, 1, or 2. Note that values greater than 1 may be + incompatible with older versions of Git which do not yet understand + those versions. Use caution when operating in a mixed-version + environment. ++ +Defaults to -1. ++ +If -1, Git will use the version of the changed-path Bloom filters in the +repository, defaulting to 1 if there are none. ++ +If 0, Git will not read any Bloom filters, and will write version 1 Bloom +filters when instructed to write. ++ +If 1, Git will only read version 1 Bloom filters, and will write version 1 +Bloom filters. ++ +If 2, Git will only read version 2 Bloom filters, and will write version 2 +Bloom filters. ++ +See linkgit:git-commit-graph[1] for more information. diff --git a/Documentation/gitformat-commit-graph.txt b/Documentation/gitformat-commit-graph.txt index 31cad585e2..3e906e8030 100644 --- a/Documentation/gitformat-commit-graph.txt +++ b/Documentation/gitformat-commit-graph.txt @@ -142,13 +142,16 @@ All multi-byte numbers are in network byte order. ==== Bloom Filter Data (ID: {'B', 'D', 'A', 'T'}) [Optional] * It starts with header consisting of three unsigned 32-bit integers: - - Version of the hash algorithm being used. We currently only support - value 1 which corresponds to the 32-bit version of the murmur3 hash + - Version of the hash algorithm being used. We currently support + value 2 which corresponds to the 32-bit version of the murmur3 hash implemented exactly as described in https://en.wikipedia.org/wiki/MurmurHash#Algorithm and the double hashing technique using seed values 0x293ae76f and 0x7e646e2 as described in https://doi.org/10.1007/978-3-540-30494-4_26 "Bloom Filters - in Probabilistic Verification" + in Probabilistic Verification". Version 1 Bloom filters have a bug that appears + when char is signed and the repository has path names that have characters >= + 0x80; Git supports reading and writing them, but this ability will be removed + in a future version of Git. - The number of times a path is hashed and hence the number of bit positions that cumulatively determine whether a file is present in the commit. - The minimum number of bits 'b' per entry in the Bloom filter. If the filter |