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 [mailtogman@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.
>
> --------------------------------------------------------------


---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match

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@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 [mailtogman@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 3: Have you checked our extensive FAQ?

http://www.postgresql.org/docs/faq

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?

---------------------------------------------------------------------------


>
> 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 [mailtogman@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
>

--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend

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 [mailtogman@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)

---------------------------(end of broadcast)---------------------------
TIP 6: explain analyze is your friend

I think the patch is ok now, intervall is not failing anymore as of
18:50 CET.

However stats fails.
regression.diffs:

*** ./expected/stats.out Sat Jul 23 17:18:20 2005
--- ./results/stats.out Sat Jul 23 18:55:17 2005
***************
*** 53,59 ****
WHERE st.relname='tenk2' AND cl.relname='tenk2';
?column? | ?column? | ?column? | ?column?
----------+----------+----------+----------
! t | t | t | t
(1 row)

SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
--- 53,59 ----
WHERE st.relname='tenk2' AND cl.relname='tenk2';
?column? | ?column? | ?column? | ?column?
----------+----------+----------+----------
! f | f | t | t
(1 row)

SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
***************
*** 62,68 ****
WHERE st.relname='tenk2' AND cl.relname='tenk2';
?column? | ?column?
----------+----------
! t | t
(1 row)

-- End of Stats Test
--- 62,68 ----
WHERE st.relname='tenk2' AND cl.relname='tenk2';
?column? | ?column?
----------+----------
! f | t
(1 row)

-- End of Stats Test

================================================== ====================

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?
>
> ---------------------------------------------------------------------------
>
>
> >
> > 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 [mailtogman@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)

---------------------------(end of broadcast)---------------------------
TIP 2: Don't 'kill -9' the postmaster

Yes, we have seen those stat tests fail randomly. We are working on a
solution.


---------------------------------------------------------------------------

ohp@pyrenet.fr wrote:
> I think the patch is ok now, intervall is not failing anymore as of
> 18:50 CET.
>
> However stats fails.
> regression.diffs:
>
> *** ./expected/stats.out Sat Jul 23 17:18:20 2005
> --- ./results/stats.out Sat Jul 23 18:55:17 2005
> ***************
> *** 53,59 ****
> WHERE st.relname='tenk2' AND cl.relname='tenk2';
> ?column? | ?column? | ?column? | ?column?
> ----------+----------+----------+----------
> ! t | t | t | t
> (1 row)
>
> SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
> --- 53,59 ----
> WHERE st.relname='tenk2' AND cl.relname='tenk2';
> ?column? | ?column? | ?column? | ?column?
> ----------+----------+----------+----------
> ! f | f | t | t
> (1 row)
>
> SELECT st.heap_blks_read + st.heap_blks_hit >= pr.heap_blks + cl.relpages,
> ***************
> *** 62,68 ****
> WHERE st.relname='tenk2' AND cl.relname='tenk2';
> ?column? | ?column?
> ----------+----------
> ! t | t
> (1 row)
>
> -- End of Stats Test
> --- 62,68 ----
> WHERE st.relname='tenk2' AND cl.relname='tenk2';
> ?column? | ?column?
> ----------+----------
> ! f | t
> (1 row)
>
> -- End of Stats Test
>
> ================================================== ====================
>
> 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?
> >
> > ---------------------------------------------------------------------------
> >
> >
> > >
> > > 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 [mailtogman@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)
>

--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073

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Would you please try the attached patch and let me know if it fixes the
problem? I avoided accumulating into a float8.

---------------------------------------------------------------------------

Rocco Altier wrote:
> 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 [mailtogman@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.
> >
> > --------------------------------------------------------------
>
>
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>

--
Bruce Momjian | http://candle.pha.pa.us
pgman@candle.pha.pa.us | (610) 359-1001
+ If your life is a hard drive, | 13 Roberts Road
+ Christ can be your backup. | Newtown Square, Pennsylvania 19073


Index: src/backend/utils/adt/timestamp.c
================================================== =================
RCS file: /cvsroot/pgsql/src/backend/utils/adt/timestamp.c,v
retrieving revision 1.145
diff -c -c -r1.145 timestamp.c
*** src/backend/utils/adt/timestamp.c 23 Jul 2005 14:53:21 -0000 1.145
--- src/backend/utils/adt/timestamp.c 23 Jul 2005 18:45:56 -0000
***************
*** 2309,2327 ****
result->time = span->time / factor;

/* Compute remainders */
! month_remainder = span->month / factor - result->month;
! day_remainder = span->day / factor - result->day;

/* Cascade fractions to lower units */
/* fractional months full days into days */
result->day += month_remainder * DAYS_PER_MONTH;
- /* fractional months partial days into time */
- day_remainder += (month_remainder * DAYS_PER_MONTH) - (int)(month_remainder * DAYS_PER_MONTH);

#ifdef HAVE_INT64_TIMESTAMP
! result->time += day_remainder * USECS_PER_DAY;
#else
! result->time += day_remainder * SECS_PER_DAY;
result->time = JROUND(result->time);
#endif

--- 2309,2328 ----
result->time = span->time / factor;

/* Compute remainders */
! month_remainder = (span->month / factor - result->month);
! day_remainder = (span->day / factor - result->day);

/* Cascade fractions to lower units */
/* fractional months full days into days */
result->day += month_remainder * DAYS_PER_MONTH;

+ /* fractional months partial days into time */
#ifdef HAVE_INT64_TIMESTAMP
! result->time += (day_remainder + month_remainder * DAYS_PER_MONTH -
! (int)(month_remainder * DAYS_PER_MONTH)) * USECS_PER_DAY;
#else
! result->time += (day_remainder + month_remainder * DAYS_PER_MONTH -
! (int)(month_remainder * DAYS_PER_MONTH)) * SECS_PER_DAY;
result->time = JROUND(result->time);
#endif



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