1                     Mercurial      git                     BK (*)

     2 storage             revlog delta   compressed revisions    SCCS weave

     3 storage naming      by filename    by revision hash        by filename

     4 merge               file DAGs      changeset DAG           file DAGs?

     5 consistency         SHA1           SHA1                    CRC

     6 signable?           yes            yes                     no

     7 

     8 retrieve file tip   O(1)           O(1)                    O(revs)

     9 add rev             O(1)           O(1)                    O(revs)

    10 find prev file rev  O(1)           O(changesets)           O(revs)

    11 annotate file       O(revs)        O(changesets)           O(revs)

    12 find file changeset O(1)           O(changesets)           ?

    13 

    14 checkout            O(files)       O(files)                O(revs)?

    15 commit              O(changes)     O(changes)              ?

    16                     6 patches/s    6 patches/s             slow

    17 diff working dir    O(changes)     O(changes)              ?

    18                     < 1s           < 1s                    ?

    19 tree diff revs      O(changes)     O(changes)              ?

    20                     < 1s           < 1s                    ?

    21 hardlink clone      O(files)       O(revisions)            O(files)

    22 

    23 find remote csets   O(log new)     rsync: O(revisions)     ?

    24                                    git-http: O(changesets)

    25 pull remote csets   O(patch)       O(modified files)       O(patch)

    26 

    27 repo growth         O(patch)       O(revisions)            O(patch)

    28  kernel history     300M           3.5G?                   250M?

    29 lines of code       2500           6500 (+ cogito)         ??

    30 

    31 * I've never used BK so this is just guesses