comparison mercurial/revlog.py @ 38640:f62b8fb0a484

revlog: document and test _slicechunk

38639:2dd4cf273804

def _slicechunk(revlog, revs):
    """slice revs to reduce the amount of unrelated data to be read from disk.

    ``revs`` is sliced into groups that should be read in one time.
    Assume that revs are sorted.
    """
    start = revlog.start
    length = revlog.length

    if len(revs) <= 1:

38640:f62b8fb0a484

def _slicechunk(revlog, revs):
    """slice revs to reduce the amount of unrelated data to be read from disk.

    ``revs`` is sliced into groups that should be read in one time.
    Assume that revs are sorted.

    The initial chunk is sliced until the overall density (payload/chunks-span
    ratio) is above `revlog._srdensitythreshold`. No gap smaller than
    `revlog._srmingapsize` is skipped.

    >>> revlog = _testrevlog([
    ...  5,  #00 (5)
    ...  10, #01 (5)
    ...  12, #02 (2)
    ...  12, #03 (empty)
    ...  27, #04 (15)
    ...  31, #05 (4)
    ...  31, #06 (empty)
    ...  42, #07 (11)
    ...  47, #08 (5)
    ...  47, #09 (empty)
    ...  48, #10 (1)
    ...  51, #11 (3)
    ...  74, #12 (23)
    ...  85, #13 (11)
    ...  86, #14 (1)
    ...  91, #15 (5)
    ... ])

    >>> list(_slicechunk(revlog, range(16)))
    [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15]]
    >>> list(_slicechunk(revlog, [0, 15]))
    [[0], [15]]
    >>> list(_slicechunk(revlog, [0, 11, 15]))
    [[0], [11], [15]]
    >>> list(_slicechunk(revlog, [0, 11, 13, 15]))
    [[0], [11, 13, 15]]
    >>> list(_slicechunk(revlog, [1, 2, 3, 5, 8, 10, 11, 14]))
    [[1, 2], [5, 8, 10, 11], [14]]
    """
    start = revlog.start
    length = revlog.length

    if len(revs) <= 1: