Mercurial > hg
view tests/test-diffstat.t @ 27475:a2e2a8fa5fd1
revlog: avoid string slice when decompressing u* chunks
Revlog chunks can be stored uncompressed. If the first byte of the
raw data is \0, we store the data as is. Else we prefix it with 'u'.
Before, we performed a string slice to strip out the 'u' prefix.
With this patch, we use a buffer to avoid an extra memory copy and
associated garbage collection overhead.
I was unable to verify any performance impact of this patch. For both
mozilla-central and the hg repos, the number of manifest revisions
with 'u' prefixes is very small - under 1%. So this change likely
isn't called enough to have an impact on manifest reading. However,
the reasoning behind this change is solid, so it should be safe.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Sun, 20 Dec 2015 16:00:27 -0800 |
parents | 2e0301ac5c91 |
children | 0e29ce16ec38 |
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$ hg init repo $ cd repo $ i=0; while [ "$i" -lt 213 ]; do echo a >> a; i=`expr $i + 1`; done $ hg add a $ cp a b $ hg add b Wide diffstat: $ hg diff --stat a | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ b | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 426 insertions(+), 0 deletions(-) diffstat width: $ COLUMNS=24 hg diff --config ui.interactive=true --stat a | 213 ++++++++++++++ b | 213 ++++++++++++++ 2 files changed, 426 insertions(+), 0 deletions(-) $ hg ci -m adda $ cat >> a <<EOF > a > a > a > EOF Narrow diffstat: $ hg diff --stat a | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) $ hg ci -m appenda >>> open("c", "wb").write("\0") $ touch d $ hg add c d Binary diffstat: $ hg diff --stat c | Bin 1 files changed, 0 insertions(+), 0 deletions(-) Binary git diffstat: $ hg diff --stat --git c | Bin d | 0 2 files changed, 0 insertions(+), 0 deletions(-) $ hg ci -m createb >>> open("file with spaces", "wb").write("\0") $ hg add "file with spaces" Filename with spaces diffstat: $ hg diff --stat file with spaces | Bin 1 files changed, 0 insertions(+), 0 deletions(-) Filename with spaces git diffstat: $ hg diff --stat --git file with spaces | Bin 1 files changed, 0 insertions(+), 0 deletions(-) diffstat within directories: $ hg rm -f 'file with spaces' $ mkdir dir1 dir2 $ echo new1 > dir1/new $ echo new2 > dir2/new $ hg add dir1/new dir2/new $ hg diff --stat dir1/new | 1 + dir2/new | 1 + 2 files changed, 2 insertions(+), 0 deletions(-) $ hg diff --stat --root dir1 new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root dir1 dir2 warning: dir2 not inside relative root dir1 $ hg diff --stat --root dir1 -I dir1/old $ cd dir1 $ hg diff --stat . dir1/new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root . new | 1 + 1 files changed, 1 insertions(+), 0 deletions(-) $ hg diff --stat --root ../dir1 ../dir2 warning: ../dir2 not inside relative root . (glob) $ hg diff --stat --root . -I old $ cd ..