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d1b9b76734
If you run a log with diffs (such as -p, --raw, --stat etc.) the current code ends up loading many objects twice. For example, for 'log -3000 -p' my instrumentation said the objects loaded more than once are distributed as follows: 2008 blob 2103 commit 2678 tree Fixing blobs and trees will be harder, because those are really used within the diff engine and need some form of caching. However, fixing the commits is easy at least at the band-aid level. They are triggered by log_tree_diff() invoking diff_tree_sha1() on commits, which duly loads the specified object to dereference it to a tree. Since log_tree_diff() knows that it works with commits and they must have trees, we can simply pass through the trees. We add some parse_commit() calls. The ones for the parents are required; we do not know at this stage if they have been looked at. The one for the commit itself is pure paranoia, but has about the same cost as an assertion on commit->object.parsed. This has a quite dramatic effect on log --raw, though only a negligible impact on log -p: Test this tree HEAD -------------------------------------------------------------------- 4000.2: log --raw -3000 0.50(0.43+0.06) 0.54(0.46+0.06) +7.0%*** 4000.3: log -p -3000 2.34(2.20+0.13) 2.37(2.22+0.13) +1.2% -------------------------------------------------------------------- Significance hints: '.' 0.1 '*' 0.05 '**' 0.01 '***' 0.001 Signed-off-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Thomas Rast <trast@inf.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
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Git - the stupid content tracker
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"git" can mean anything, depending on your mood.
- random three-letter combination that is pronounceable, and not
actually used by any common UNIX command. The fact that it is a
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Git is a fast, scalable, distributed revision control system with an
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See Documentation/gittutorial.txt to get started, then see
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If git has been correctly installed, then the tutorial can also be
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("man gitcvs-migration" or "git help cvs-migration" if git is
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