Hi, [this explains what Patch 6/6 is all about:] If GIT_NOTES_TIMING_TESTS is set, t3302 will output some timing data. It will create three repositories, the first with 10 commits and a commit note for each, the second with 100, the third with 1000. For each repository, it times "git log" 100 times in several modes: - with GIT_NOTES_REF set to a non-existing ref (should be equivalent to the timings without this patch series), - with no .git/notes-index, - recreating .git/notes-index as a hash map _every_ time, - creating .git/notes-index as a hash map, and using it the rest of the time, - recreating .git/notes-index as a sorted list _every_ time, and - creating .git/notes-index as a sorted list only the first time, and then using it to find the notes by binary search. Here is the output: * expecting success: create_repo 10 * ok 1: setup 10 * expecting success: test_notes 10 diff --git a/expect b/output * ok 2: notes work * expecting success: time_notes 100 no-notes 0.13user 0.08system 0:00.22elapsed 98%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+45271minor)pagefaults 0swaps no-cash 0.14user 0.13system 0:00.28elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+49421minor)pagefaults 0swaps hash-cache-create 0.16user 0.24system 0:00.41elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+73111minor)pagefaults 0swaps hash-cache 0.10user 0.08system 0:00.18elapsed 101%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+45660minor)pagefaults 0swaps sorted-list-cache-create 0.23user 0.17system 0:00.40elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+72056minor)pagefaults 0swaps sorted-list-cache 0.12user 0.08system 0:00.20elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+46854minor)pagefaults 0swaps * ok 3: notes timing * expecting success: create_repo 100 * ok 1: setup 100 * expecting success: test_notes 100 diff --git a/expect b/output * ok 2: notes work * expecting success: time_notes 100 no-notes 0.38user 0.18system 0:00.56elapsed 100%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+54386minor)pagefaults 0swaps no-cash 1.45user 0.66system 0:02.13elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+93980minor)pagefaults 0swaps hash-cache-create 1.56user 0.98system 0:02.56elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+132604minor)pagefaults 0swaps hash-cache 0.38user 0.17system 0:00.56elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+54785minor)pagefaults 0swaps sorted-list-cache-create 1.56user 0.88system 0:02.47elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+124215minor)pagefaults 0swaps sorted-list-cache 0.44user 0.23system 0:00.68elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+64952minor)pagefaults 0swaps * ok 3: notes timing * expecting success: create_repo 1000 * ok 1: setup 1000 * expecting success: test_notes 1000 diff --git a/expect b/output * ok 2: notes work * expecting success: time_notes 100 no-notes 2.95user 1.19system 0:04.18elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+144766minor)pagefaults 0swaps no-cash 23.05user 5.86system 0:33.06elapsed 87%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+639774minor)pagefaults 0swaps hash-cache-create 23.86user 7.21system 0:32.67elapsed 95%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+710958minor)pagefaults 0swaps hash-cache 3.16user 1.18system 0:04.35elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+145160minor)pagefaults 0swaps sorted-list-cache-create 23.22user 7.32system 0:31.66elapsed 96%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+686007minor)pagefaults 0swaps sorted-list-cache 3.74user 1.81system 0:05.77elapsed 96%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+241987minor)pagefaults 0swaps * ok 3: notes timing Results: These timings were taken from a desktop machine with a few background processes running, so take them with a grain of salt. As expected, without a .git/notes-index, it scales pretty badly. Creating .git/notes-index is slightly worse than that, but it typically happens much less often than looking at a commit message. Therefore the work is worth it, since the lookup _with_ .git/notes-index is in the same ball park as no notes at all, with the hash map being better than the sorted list lookup. Therefore I will go with the hash map approach, when cleaning up patch 6/6. But not tonight. Ciao, Dscho - 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
