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

On 04/13/2012 06:22 PM, Tom Lane wrote:
> But (a) I *don't* want to seriously break things, and don't see a need
> to; (b) interval is expensive and has got its own problems, notably an
> internal limitation to usec resolution that we would not be able to get
> rid of easily.

A straight float seems pretty future proof compared to a usec resolution 
interval.  Jim was commenting in the same direction I already did, that 
ns resolution is not impossible to see coming.

I also expect to compute plenty of derived statistics from these 
numbers.  Interval math is good enough that I'm sure such things could 
be done, but it seems odd to start with those units.  I appreciate that 
the interval type has a nice purist feel to it.  My pragmatic side says 
we're going to pay overhead to create in that type, only to find people 
end up converting it right back to other types for easier math tricks.

-- 
Greg Smith   2ndQuadrant US    greg@2ndQuadrant.com   Baltimore, MD
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