From a33fc72fe911fdb8e284c94e08e8f1dafe4d3187 Mon Sep 17 00:00:00 2001 From: Jeff Hostetler Date: Fri, 14 Apr 2017 20:32:21 +0000 Subject: read-cache: force_verify_index_checksum Teach git to skip verification of the SHA1-1 checksum at the end of the index file in verify_hdr() which is called from read_index() unless the "force_verify_index_checksum" global variable is set. Teach fsck to force this verification. The checksum verification is for detecting disk corruption, and for small projects, the time it takes to compute SHA-1 is not that significant, but for gigantic repositories this calculation adds significant time to every command. These effect can be seen using t/perf/p0002-read-cache.sh: Test HEAD~1 HEAD -------------------------------------------------------------------------------------- 0002.1: read_cache/discard_cache 1000 times 0.66(0.44+0.20) 0.30(0.27+0.02) -54.5% Signed-off-by: Jeff Hostetler Signed-off-by: Junio C Hamano --- t/t1450-fsck.sh | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 't') diff --git a/t/t1450-fsck.sh b/t/t1450-fsck.sh index 33a51c9a67..677e15a7a4 100755 --- a/t/t1450-fsck.sh +++ b/t/t1450-fsck.sh @@ -689,4 +689,17 @@ test_expect_success 'bogus head does not fallback to all heads' ' ! grep $blob out ' +test_expect_success 'detect corrupt index file in fsck' ' + cp .git/index .git/index.backup && + test_when_finished "mv .git/index.backup .git/index" && + echo zzzzzzzz >zzzzzzzz && + git add zzzzzzzz && + sed -e "s/zzzzzzzz/yyyyyyyy/" .git/index >.git/index.yyy && + mv .git/index.yyy .git/index && + # Confirm that fsck detects invalid checksum + test_must_fail git fsck --cache && + # Confirm that status no longer complains about invalid checksum + git status +' + test_done -- cgit v1.2.3