On Tue, Sep 06, 2022 at 02:38:41PM -0400, Jeff King wrote: > On Mon, Sep 05, 2022 at 11:17:21AM +0000, 程洋 wrote: > > > Sorry, I told you the wrong branch. It should be "android-t-preview-1" > > git clone --filter=blob:none --no-local -b android-t-preview-1 grade-plugin > > > > Can you try this one? > > Yes, I see more slow-down there. There are many more blobs there, but I > don't think it's really the number of them, but their sizes. > > The problem is that both upload-pack and pack-objects are keen to call > parse_object() on their inputs. For commits, etc, that is usually > sensible; we have to parse the object to see what it points to. But for > blobs, the only thing we do is inflate a ton of bytes in order to check > the sha1. That's not really productive here; if there is a bit > corruption, the client will notice it on the receiving side. So here's a cleaned-up series which makes this a lot faster. The special sauce is in patch 2, along with timings. The first one is just preparing, and the final one is a small cleanup it enables. I based these directly on the current tip of master. There will be a small conflict in the test script when merging with the "rev-list --verify-objects" series I just sent in: https://lore.kernel.org/git/Yxe0k++LA%2FUfFLF%2F@xxxxxxxxxxxxxxxxxxxxxxx/ The resolution is to just keep the tests added by both sides. [1/3]: parse_object(): allow skipping hash check [2/3]: upload-pack: skip parse-object re-hashing of "want" objects [3/3]: parse_object(): check commit-graph when skip_hash set object.c | 21 ++++++++++++++++++--- object.h | 6 ++++++ revision.c | 14 +++----------- t/t1450-fsck.sh | 20 ++++++++++++++++++++ upload-pack.c | 8 ++------ 5 files changed, 49 insertions(+), 20 deletions(-) -Peff
