Re: [HACKERS] regressin failure on latest CVS

I just checked latest CVS (5 mn ago) the problem is still the same,
BTW, this is on Unixware 714 and no --enable-integer-datetime

Regards
On Sat, 23 Jul 2005, Rocco Altier wrote:

> Date: Sat, 23 Jul 2005 11:15:44 -0400
> From: Rocco Altier <RoccoA(at)Routescape(dot)com>
> To: Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>
> Cc: Michael Glaesemann <grzm(at)myrealbox(dot)com>, pgsql-patches(at)postgresql(dot)org,
> pgsql-hackers(at)postgresql(dot)org, ohp(at)pyrenet(dot)fr
> Subject: RE: [HACKERS] regressin failure on latest CVS
>
> This still does not fix the problem.
>
> I had done my patch to try to mimic the way 8.0 had handled the math
> with the remainders, but to carry it over another bucket (day).
>
> The problem that I see is that we are taking day_remainder and
> multiplying by USECS_PER_DAY. Which is a double * int64, thus there is
> the precision loss there.
>
> I think initial division by the factor can't be helped, but repeatedly
> doing more floating point math on with it is causing the rounding error.
>
> Thanks,
> -rocco
>
> > -----Original Message-----
> > From: Bruce Momjian [mailto:pgman(at)candle(dot)pha(dot)pa(dot)us]
> > Sent: Saturday, July 23, 2005 10:54 AM
> > To: Rocco Altier
> > Cc: Michael Glaesemann; pgsql-patches(at)postgresql(dot)org;
> > pgsql-hackers(at)postgresql(dot)org; ohp(at)pyrenet(dot)fr
> > Subject: Re: [HACKERS] regressin failure on latest CVS
> >
> >
> > Rocco Altier wrote:
> > > This patch fixes the interval regression on my AIX box
> > (kookaburra) by
> > > only doing integer math on the interval, instead of
> > float/double math.
> > >
> > > I think this is the correct way to handle this, since it's
> > an integer
> > > data type.
> > >
> > > I don't know if it will fix Olivier's problem, since I
> > wasn't able to
> > > reproduce it.
> > >
> >
> > I have changed the way I compute the remainder values --- instead of
> > using multiplication, I use division and then subtraction.
> > This should
> > fix your rounding problem. Looking at your fix, I don't see
> > how adding
> > USECS changes things because the factor is already a float,
> > but I think
> > the problem was more the way I was computing the remainders.
> >
> > Patch attached --- let me know if it does not fix your problem.
> >
> > --------------------------------------------------------------
>
>
>

--
Olivier PRENANT Tel: +33-5-61-50-97-00 (Work)
15, Chemin des Monges +33-5-61-50-97-01 (Fax)
31190 AUTERIVE +33-6-07-63-80-64 (GSM)
FRANCE Email: ohp(at)pyrenet(dot)fr
------------------------------------------------------------------------------
Make your life a dream, make your dream a reality. (St Exupery)