Since commit 2f82f760 (Take binary diffs into
account for "git rebase"), binary files are
included in patch ID computation. Binary files are
diffed using the text diff algorithm, however,
which has a huge impact on performance. The
following tests performance for a 50000 line file
marked as binary in .gitattributes.
$ git format-patch --stdout --ignore-if-in-upstream master
real 0m0.367s
user 0m0.354s
sys 0m0.010s
Instead of diffing the binary files, hash the pre-
and post-image sha1, which is just as unique. As a
result, performance is much improved.
$ git format-patch --stdout --ignore-if-in-upstream master
real 0m0.016s
user 0m0.015s
sys 0m0.001s
Signed-off-by: Clemens Buchacher <drizzd@xxxxxx>
---
I am again attaching the corresponding test script. Since it mostly
tests performance, I am not sure how to incorporate it into the
main test suite.
diff.c | 7 +++++++
1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/diff.c b/diff.c
index 17873f3..f4a23ab 100644
--- a/diff.c
+++ b/diff.c
@@ -3758,6 +3758,13 @@ static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
len2, p->two->path);
git_SHA1_Update(&ctx, buffer, len1);
+ if (diff_filespec_is_binary(p->one) ||
+ diff_filespec_is_binary(p->two)) {
+ git_SHA1_Update(&ctx, sha1_to_hex(p->one->sha1), 40);
+ git_SHA1_Update(&ctx, sha1_to_hex(p->two->sha1), 40);
+ continue;
+ }
+
xpp.flags = 0;
xecfg.ctxlen = 3;
xecfg.flags = XDL_EMIT_FUNCNAMES;
--
1.7.2.1.1.g202c
Attachment:
test-patchid.sh
Description: Bourne shell script
Attachment:
signature.asc
Description: Digital signature