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. -Peff
