It looks like it's a file caching effect combined with my repo being more pathalogical in size and contents. Note run 1 (cold) vs run 2 on the linux file tree: 13:52 ajb@sloy/x86_64 [linux.git] >time git describe --debug --long --tags HEAD~10000 searching to describe HEAD~10000 annotated 57 v2.6.34-rc2 annotated 1688 v2.6.34-rc1 annotated 7932 v2.6.33 annotated 8157 v2.6.33-rc8 annotated 8381 v2.6.33-rc7 annotated 8637 v2.6.33-rc6 annotated 8964 v2.6.33-rc5 annotated 9493 v2.6.33-rc4 annotated 9912 v2.6.33-rc3 annotated 10202 v2.6.33-rc2 traversed 10547 commits more than 10 tags found; listed 10 most recent gave up search at 55639353a0035052d9ea6cfe4dde0ac7fcbb2c9f v2.6.34-rc2-57-gef5da59 real 0m7.332s user 0m0.308s sys 0m0.244s 14:03 ajb@sloy/x86_64 [linux.git] >time git describe --debug --long --tags HEAD~10000 searching to describe HEAD~10000 annotated 57 v2.6.34-rc2 annotated 1688 v2.6.34-rc1 annotated 7932 v2.6.33 annotated 8157 v2.6.33-rc8 annotated 8381 v2.6.33-rc7 annotated 8637 v2.6.33-rc6 annotated 8964 v2.6.33-rc5 annotated 9493 v2.6.33-rc4 annotated 9912 v2.6.33-rc3 annotated 10202 v2.6.33-rc2 traversed 10547 commits more than 10 tags found; listed 10 most recent gave up search at 55639353a0035052d9ea6cfe4dde0ac7fcbb2c9f v2.6.34-rc2-57-gef5da59 real 0m0.298s user 0m0.244s sys 0m0.036s Although the perf profile looks subtly different. First through the linux tree: 22.35% git libz.so.1.2.3.4 [.] inflate 18.56% git libz.so.1.2.3.4 [.] inflate_fast 17.48% git libz.so.1.2.3.4 [.] inflate_table 7.84% git git [.] hashcmp 3.93% git git [.] get_sha1_hex 3.46% git libz.so.1.2.3.4 [.] adler32 And through my "special" repo: 41.58% git libcrypto.so.1.0.0 [.] sha1_block_data_order_ssse3 33.62% git libz.so.1.2.3.4 [.] inflate_fast 10.39% git libz.so.1.2.3.4 [.] adler32 2.03% git [kernel.kallsyms] [k] clear_page_c I'm not sure why libcrypto features so highly in the results -- Alex. On 30 May 2013 12:33, Ramkumar Ramachandra <artagnon@xxxxxxxxx> wrote: > Alex Bennée wrote: >>>time /usr/bin/git --no-pager >> traversed 223 commits >> >> real 0m4.817s >> user 0m4.320s >> sys 0m0.464s > > I'm quite clueless about why it is taking this long: I think it's IO > because there's nothing to compute? I really can't trace anything > unless you can reproduce it on a public repository. On linux.git with > my rotating hard disk: > > $ time git describe --debug --long --tags HEAD~10000 > searching to describe HEAD~10000 > annotated 5445 v2.6.33 > annotated 5660 v2.6.33-rc8 > annotated 5884 v2.6.33-rc7 > annotated 6140 v2.6.33-rc6 > annotated 6467 v2.6.33-rc5 > annotated 6999 v2.6.33-rc4 > annotated 7430 v2.6.33-rc3 > annotated 7746 v2.6.33-rc2 > annotated 8212 v2.6.33-rc1 > annotated 13854 v2.6.32 > traversed 18895 commits > more than 10 tags found; listed 10 most recent > gave up search at 648f4e3e50c4793d9dbf9a09afa193631f76fa26 > v2.6.33-5445-ge7c84ee > > real 0m0.509s > user 0m0.470s > sys 0m0.037s > > 18k+ commits traversed in half a second here, so I really don't know > what is going on. -- Alex, homepage: http://www.bennee.com/~alex/ -- 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