On 9/6/2022 6:58 PM, Jeff King wrote: > 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. Thanks for finding this very subtle issue! > 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 carefully read these patches as well as applied them on my machine and did some extra digging and performance tests to understand the change. LGTM. Thanks, -Stolee
