Re: Reduce heap tuple header size

Alvaro Herrera wrote:
> Tom Lane dijo:
>
> > Jan Wieck <JanWieck@Yahoo.com> writes:
> > > Here are some numbers:
> >
> > > Current CVS tip:     tps  34.1, 38.7, 36.6
> > >                  avg(tps) 36.4
> >
> > > With patch:          tps  37.0, 41.1, 41.1
> > >                  avg(tps) 39.7
> >
> > > So it saves less than 3% disk space at the cost of about 9% performance
> > > loss.
> >
> > Uh ... isn't more TPS better?

9%, that is a dramatic difference.  Is it caused by the reduced disk
space (Jan's numbers are correct) or by the extra overhead in the merged
fields (Jan's numbers are backwards)?  Jan will tell us soon.

> Also, is that 3% in disk space savings the actual number, or just copied
> from the "anawhat"?

The 3% is savings from a sample database.  Header size is 11% reduced.

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