Re: [HACKERS] regressin failure on latest CVS - Mailing list pgsql-patches

On Sat, 23 Jul 2005, Bruce Momjian wrote:

> Date: Sat, 23 Jul 2005 11:36:43 -0400 (EDT)
> From: Bruce Momjian <pgman@candle.pha.pa.us>
> To: ohp@pyrenet.fr
> Cc: Rocco Altier <RoccoA@Routescape.com>,
>      Michael Glaesemann <grzm@myrealbox.com>, pgsql-patches@postgresql.org,
>      pgsql-hackers@postgresql.org
> Subject: Re: [HACKERS] regressin failure on latest CVS
>
> ohp@pyrenet.fr wrote:
> > 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
>
> Do you have the latest patch included int that version of CVS?
> Anonymous CVS has a delay, and what was the problem you were seeing, the
> rounding or the day - 1 result?
>
I was seeing (and still see) the day -1 result. However, if I ./configure
--with-integer-datetimes I see the rounding of the day.
> ---------------------------------------------------------------------------
>
>
> >
> > Regards
> > On Sat, 23 Jul 2005, Rocco Altier wrote:
> >
> > > Date: Sat, 23 Jul 2005 11:15:44 -0400
> > > From: Rocco Altier <RoccoA@Routescape.com>
> > > To: Bruce Momjian <pgman@candle.pha.pa.us>
> > > Cc: Michael Glaesemann <grzm@myrealbox.com>, pgsql-patches@postgresql.org,
> > >      pgsql-hackers@postgresql.org, ohp@pyrenet.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@candle.pha.pa.us]
> > > > Sent: Saturday, July 23, 2005 10:54 AM
> > > > To: Rocco Altier
> > > > Cc: Michael Glaesemann; pgsql-patches@postgresql.org;
> > > > pgsql-hackers@postgresql.org; ohp@pyrenet.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@pyrenet.fr
> > ------------------------------------------------------------------------------
> > Make your life a dream, make your dream a reality. (St Exupery)
> >
> > ---------------------------(end of broadcast)---------------------------
> > TIP 6: explain analyze is your friend
> >
>
>

--
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@pyrenet.fr
------------------------------------------------------------------------------
Make your life a dream, make your dream a reality. (St Exupery)