| commit | 7b8a21dba1bce44d64bd86427d3d92437adc4707 | [log] [tgz] |
|---|---|---|
| author | Derrick Stolee <dstolee@microsoft.com> | Fri Apr 06 19:09:46 2018 +0000 |
| committer | Junio C Hamano <gitster@pobox.com> | Wed Apr 11 10:47:16 2018 +0900 |
| tree | e45261ae8a002fdd4bab8ffc632740b5cee55c8c | |
| parent | 2e27bd7731d47b374c1c14b53af07b3bfa39fcac [diff] |
commit-graph: lazy-load trees for commits
The commit-graph file provides quick access to commit data, including
the OID of the root tree for each commit in the graph. When performing
a deep commit-graph walk, we may not need to load most of the trees
for these commits.
Delay loading the tree object for a commit loaded from the graph
until requested via get_commit_tree(). Do not lazy-load trees for
commits not in the graph, since that requires duplicate parsing
and the relative peformance improvement when trees are not needed
is small.
On the Linux repository, performance tests were run for the following
command:
git log --graph --oneline -1000
Before: 0.92s
After: 0.66s
Rel %: -28.3%
Adding '-- kernel/' to the command requires loading the root tree
for every commit that is walked. There was no measureable performance
change as a result of this patch.
Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
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