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    SubjectRe: Interesting scheduling times - NOT
    Larry McVoy wrote:
    >
    > Just to put to rest the idea that maybe the median is covering things
    > up, here's the full set of data, note the small standard deviation:
    >
    > 2 7.58 (7.74 7.65 7.63 7.60 7.60 7.58 7.58 7.58 7.55 7.54 7.53)
    >
    > Here's the same thing with each run taking 500 milliseconds (so a total of
    > about 6 seconds of run time):
    >
    > 2 7.73 (8.38 8.14 8.13 8.00 7.94 7.73 7.62 7.60 7.46 7.33 7.04)
    >

    Just to scroll things back a few days here guys: (I just noticed this
    message in my backlog)

    Anybody else notice that Larry's results are monotonic on both sets of
    data ? The chances against monotonicity for each run are 2^9 to 1
    against.

    This says VERY loudly that these are not random differences - something
    else is happening. That something else appears to dwarf the random
    effects that are probably present, because monotonicity isn't violated
    even a single time.

    Then compare first and last entries for the second run and you get a
    non-trivial difference...

    The fact that the times are varying even until the end of each run says
    that something hasn't equilibrated (probably a cache thing) and that
    drawing conclusions from the results is subject to some dangers.

    And yeah, the median certainly covered *that* thing up, no?

    Comments?

    Neil

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