Re: Patch: add timing of buffer I/O requests

On Wed, Apr 25, 2012 at 1:58 PM, Greg Stark <stark(at)mit(dot)edu> wrote:
> On Wed, Apr 25, 2012 at 5:47 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> Also, as was pointed out upthread, the underlying data in shared memory
>> is almost certainly never going to be infinite-precision; so using
>> numeric in the API seems to me to be more likely to convey a false
>> impression of exactness than to do anything useful.
>
> I don't think that follows. The underlyng data will be measured in
> some metric unit of time like microsecond or nanosecond or something
> like that. So a base-10 representation will show exactly the precision
> that the underlying data has. On the other hand a floating point
> number will show a base-2 approximation that may in fact display with
> more digits than the underlying data representation has.

I wholeheartedly agree.

--
Robert Haas
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