https://gerrit.googlesource.com/jgit/+/refs/heads/master/org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java#2037 It seems you're right. According to commnet I found in jgit source code. It seems it is indeed doing what you said! > On 8/14/2022 2:48 AM, Jeff King wrote: > > On Thu, Aug 11, 2022 at 08:09:56AM +0000, 程洋 wrote: > > > >> 4. And we then track our server(which is gerrit with jgit). We > >> found the server is couting objects. Then we check those 40k > >> objects, most of them are blobs rather than commit. (which > >> means they're not in bitmap) > >> 5. We believe that's the root cause of our problem. Git sends too > >> many "want SHA1" which are not in bitmap, cause the server to > >> count objects frequently, which then slow down the server. > > > > I'd be surprised if bitmaps make a big difference either way here, > > since blobs are very quick in the "counting" phase of pack-objects. > > They can't link to anything else, so we should not be opening the > > object contents at all! We just need to find them on disk, and then in > > many cases we can send them over the wire without even decompressing > > (the exception is if they are stored as deltas against an object the client > doesn't have). > > > > I didn't generate a test case, but I'm pretty sure that is how > > git.git's pack-objects should behave. But you mentioned that the > > server is jgit; it's possible that it isn't as optimized in that area. > > I just remembered that Gerrit specifically has branch-level security, where > some branches are not visible to all users. For that reason, blobs cannot be > served without first determining if they are reachable from a branch visible > to the current user. > > I'm not sure if that's the problem in this particular case, but it could be. > > Thanks, > -Stolee #/******本邮件及其附件含有小米公司的保密信息，仅限于发送给上面地址中列出的个人或群组。禁止任何其他人以任何形式使用（包括但不限于全部或部分地泄露、复制、或散发）本邮件中的信息。如果您错收了本邮件，请您立即电话或邮件通知发件人并删除本邮件！ This e-mail and its attachments contain confidential information from XIAOMI, which is intended only for the person or entity whose address is listed above. Any use of the information contained herein in any way (including, but not limited to, total or partial disclosure, reproduction, or dissemination) by persons other than the intended recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender by phone or email immediately and delete it!******/#
