Re: patternsel() and histogram_selectivity() and the hard cutoff of 100

Hi Greg,

>> So I had a thought about how to soften the controversial hard cutoff of 100
>> for the use of the histogram selectivity. Instead of switching 100% one way or
>> the other between the two heuristics why not calculate both and combine them.
>> The larger the sample size from the histogram the more we can weight the
>> histogram calculation. The smaller the histogram size the more we weight the
>> heuristic.
>>
>> My first thought was to scale it linearly so we use 10% of the histogram
>> sample + 90% of the heuristic for default statistic sizes of 10 samples. That
>> degenerates to the status quo for 100 samples and up.
>
> Incidentally I hacked up a patch to do this:

Sounds sensible to me, at least much more than a hardcoded magic number
a few people know about...

Cheers

--
Matteo Beccati

Openads - http://www.openads.org