To elaborate from before, my repository is about 2GB and has about 7k branches and tags with 15 years of history imported from CVS. I created a toy repository attempting to replicate the problem but haven't had any luck so instead I launched Git in a debugger to see what operation is taking so long in "git clone". I stopped randomly in the middle and stepped to the line which seems to be contributing the most: #0 read_packed_sha1 (sha1=0xb0ee98 "\017C\205Wj\001`\254\356\307Z\332\367\353\233.\375P}D", type=0x7fbfffe7a4, size=0x7fbfffe798) at sha1_file.c:2237 #1 0x00000000004d366e in read_object (sha1=0xb0ee98 "\017C\205Wj\001`\254\356\307Z\332\367\353\233.\375P}D", type=0x7fbfffe7a4, size=0x7fbfffe798) at sha1_file.c:2277 #2 0x00000000004d3839 in read_sha1_file_extended (sha1=0xb0ee98 "\017C\205Wj\001`\254\356\307Z\332\367\353\233.\375P}D", type=0x7fbfffe7a4, size=0x7fbfffe798, flag=<optimized out>) at sha1_file.c:2307 #3 0x00000000004ae000 in read_sha1_file (sha1=0x7fbfffc5e0 "", type=0x6be000, size=0x2b039b9010) at cache.h:730 #4 parse_object (sha1=0xb0ee98 "\017C\205Wj\001`\254\356\307Z\332\367\353\233.\375P}D") at object.c:212 #5 0x00000000004ae9ec in handle_one_ref (path=0xb0eec0 "refs/tags/<removed>", sha1=0xb0ee98 "\017C\205Wj\001`\254\356\307Z\332\367\353\233.\375P}D", flags=2, cb_data=<optimized out>) at pack-refs. #6 0x00000000004bc402 in do_one_ref (base=<optimized out>, fn=0x4ae8f0 <handle_one_ref>, trim=<optimized out>, flags=0, cb_data=0x7fbfffe9c0, entry=0xb0ee90) at refs.c:527 #7 0x00000000004bd38b in do_for_each_ref_in_dir (dir=0xb09be8, offset=<optimized out>, base=0x4fd9b0 "", fn=0x4ae8f0 <handle_one_ref>, trim=0, flags=0, cb_data=0x7fbfffe9c0) at refs.c:553 #8 0x00000000004bd6cb in do_for_each_ref_in_dirs (dir1=0x6a8588, dir2=0xb0ab18, base=0x4fd9b0 "", fn=0x4ae8f0 <handle_one_ref>, trim=0, flags=0, cb_data=0x7fbfffe9c0) at refs.c:599 #9 0x00000000004bd6cb in do_for_each_ref_in_dirs (dir1=0x6a3118, dir2=0xb038b8, base=0x4fd9b0 "", fn=0x4ae8f0 <handle_one_ref>, trim=0, flags=0, cb_data=0x7fbfffe9c0) at refs.c:599 #10 0x00000000004bdb3f in do_for_each_ref (submodule=<optimized out>, base=0x4fd9b0 "", fn=0x4ae8f0 <handle_one_ref>, trim=0, flags=0, cb_data=0x7fbfffe9c0) at refs.c:1288 #11 0x00000000004aeaba in pack_refs (flags=<optimized out>) at pack-refs.c:133 #12 0x000000000041da30 in write_remote_refs (local_refs=<optimized out>) at builtin/clone.c:470 #13 update_remote_refs (refs=<optimized out>, mapped_refs=<optimized out>, remote_head_points_at=<optimized out>, branch_top=0x6a4210 "refs/remotes/origin/", msg=0x6a1160 "clone: from /z/umoszkow/git/clone/../merged/merged.git") at bu #14 cmd_clone (argc=<optimized out>, argv=0x7fbffff1b0, prefix=<optimized out>) at builtin/clone.c:898 #15 0x0000000000404eef in handle_internal_command (argc=3, argv=0x7fbffff1b0) at git.c:306 #16 0x0000000000405347 in run_argv (argcp=<optimized out>, argv=<optimized out>) at git.c:513 #17 main (argc=3, argv=0x7fbffff1b0) at git.c:588 It looks like handle_one_ref() is called for each ref and most result in a call to read_sha1_file(). It only takes a second or so for each call but when you have thousands of them (one for each ref) it adds up. Adding --single-branch --branch <branch> doesn't appear to help as it is implemented afterwards. I would like to debug this problem further but am not familiar enough with the implementation to know what the next step is. Can anyone offer some suggestions? I don't see why a clone should be dependent on an O(#refs) operations. On Tue, Oct 23, 2012 at 1:30 PM, Uri Moszkowicz <uri@xxxxxxxxx> wrote: > I have a large repository which I ran "git gc --aggressive" on that > I'm trying to clone on a local file system. I would expect it to > complete very quickly with hard links but it's taking about 6min to > complete with no checkout (git clone -n). I see the message "Clining > into 'repos'... done." appear after a few seconds but then Git just > hangs there for another 6min. Any idea what it's doing at this point > and how I can speed it up? -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html