On 10/21/2013 04:43 PM, Peter Geoghegan wrote:
On Mon, Oct 21, 2013 at 1:36 PM, Robert Haas <robertmh...@gmail.com> wrote:
Yeah, and I worry about min and max not being very usable - once they
get pushed out to extreme values, there's nothing to drag them back
toward normality except resetting the stats, and that's not something
we want to encourage people to do frequently.
My thoughts exactly. Perhaps it'd be useful to separately invalidate
min/max times, without a full reset. But then you've introduced the
possibility of the average time (total_time/calls) exceeding the max
or being less than the min.
This is why I suggested the standard deviation, and why I find it would
be more useful than just min and max. A couple of outliers will set the
min and max to
possibly extreme values but hardly perturb the standard deviation over a
large number of observations.
cheers
andrew
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