Re: checkpointer continuous flushing

Hi,

On 03/22/2016 10:44 AM, Fabien COELHO wrote:
>
>
>>>> 1) regular-latency.png
>>>
>>> I'm wondering whether it would be clearer if the percentiles
>>> where relative to the largest sample, not to itself, so that the
>>> figures from the largest one would still be between 0 and 1, but
>>> the other (unpatched) one would go between 0 and 0.85, that is
>>> would be cut short proportionnaly to the actual performance.
>>
>> I'm not sure what you mean by 'relative to largest sample'?
>
> You took 5% of the tx on two 12 hours runs, totaling say 85M tx on
> one and 100M tx on the other, so you get 4.25M tx from the first and
> 5M from the second.

OK

> I'm saying that the percentile should be computed on the largest one
> (5M), so that you get a curve like the following, with both curve
> having the same transaction density on the y axis, so the second one
> does not go up to the top, reflecting that in this case less
> transactions where processed.

Huh, that seems weird. That's not how percentiles or CDFs work, and I 
don't quite understand what would that tell us.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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