> > > 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. At first I also think it's some implementation bugs by jgit. However I can also reproduce it on cgit. Here is the steps, I'm not sure if you can reproduce too. 1. Clone a repository from AOSP to local machine: `git clone "https://android.googlesource.com/platform/prebuilts/gradle-plugin"` 2. try to clone from localhost using cgit server. `GIT_TRACE_PACKET=1 git clone --filter=blob:none -b master user@localhost:/home/user/repositories/gradle-plugin ` 3. During checkout phase, it also takes 15 seconds before actual downloading. It's really easy to reproduce, as long as the repository has so many blobs to checkout > > -Peff #/******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!******/#
