Thread: docfix - DELETE doesn't affect auto-analyze
I reported an incorrect description for auto-analyze in our documentation. http://archives.postgresql.org/pgsql-hackers/2007-06/msg00000.php Here is a documentation fix for it. There are the same mistakes in 8.1 and 8.2, not only in HEAD. It had been true in contrib/pg_autovacuum at 8.0, but we changed the behavior at the integration of autovacuum. Index: doc/src/sgml/maintenance.sgml =================================================================== --- doc/src/sgml/maintenance.sgml (HEAD) +++ doc/src/sgml/maintenance.sgml (fixed) @@ -533,7 +533,7 @@ <programlisting> analyze threshold = analyze base threshold + analyze scale factor * number of tuples </programlisting> - is compared to the total number of tuples inserted, updated, or deleted + is compared to the total number of tuples inserted or updated since the last <command>ANALYZE</command>. </para> Regards, --- ITAGAKI Takahiro NTT Open Source Software Center
Patch applied. Thanks. Your documentation changes can be viewed in five minutes using links on the developer's page, http://www.postgresql.org/developer/testing. --------------------------------------------------------------------------- ITAGAKI Takahiro wrote: > I reported an incorrect description for auto-analyze in our documentation. > http://archives.postgresql.org/pgsql-hackers/2007-06/msg00000.php > Here is a documentation fix for it. > > There are the same mistakes in 8.1 and 8.2, not only in HEAD. > It had been true in contrib/pg_autovacuum at 8.0, but we > changed the behavior at the integration of autovacuum. > > > Index: doc/src/sgml/maintenance.sgml > =================================================================== > --- doc/src/sgml/maintenance.sgml (HEAD) > +++ doc/src/sgml/maintenance.sgml (fixed) > @@ -533,7 +533,7 @@ > <programlisting> > analyze threshold = analyze base threshold + analyze scale factor * number of tuples > </programlisting> > - is compared to the total number of tuples inserted, updated, or deleted > + is compared to the total number of tuples inserted or updated > since the last <command>ANALYZE</command>. > </para> > > > Regards, > --- > ITAGAKI Takahiro > NTT Open Source Software Center > > > ---------------------------(end of broadcast)--------------------------- > TIP 3: Have you checked our extensive FAQ? > > http://www.postgresql.org/docs/faq -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +
Bruce Momjian <bruce@momjian.us> writes:
>> - is compared to the total number of tuples inserted, updated, or deleted
>> + is compared to the total number of tuples inserted or updated
As best I can tell, this description is even further away from the
actual CVS HEAD behavior than the previous one. The code is comparing
against
anltuples = tabentry->n_live_tuples + tabentry->n_dead_tuples -
tabentry->last_anl_tuples;
and deletions surely increase n_dead_tuples.
regards, tom lane
Bruce Momjian <bruce@momjian.us> wrote: > Patch applied. Thanks. Your documentation changes can be viewed in > five minutes using links on the developer's page, > http://www.postgresql.org/developer/testing. Thanks. Don't we need to backport it to 8.1 and 8.2? It was changed at the integration of autovacuum at 8.1. Regards, --- ITAGAKI Takahiro NTT Open Source Software Center
Tom Lane wrote: > Bruce Momjian <bruce@momjian.us> writes: > >> - is compared to the total number of tuples inserted, updated, or deleted > >> + is compared to the total number of tuples inserted or updated > > As best I can tell, this description is even further away from the > actual CVS HEAD behavior than the previous one. The code is comparing > against > > anltuples = tabentry->n_live_tuples + tabentry->n_dead_tuples - > tabentry->last_anl_tuples; > > and deletions surely increase n_dead_tuples. I think the patch is correct for 8.1 and 8.2 but is wrong for HEAD (disclaimer: I'm a bit sleepy ATM). -- Alvaro Herrera http://www.advogato.org/person/alvherre Management by consensus: I have decided; you concede. (Leonard Liu)
Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Bruce Momjian <bruce@momjian.us> writes:
> >> - is compared to the total number of tuples inserted, updated, or deleted
> >> + is compared to the total number of tuples inserted or updated
>
> As best I can tell, this description is even further away from the
> actual CVS HEAD behavior than the previous one. The code is comparing
> against
>
> anltuples = tabentry->n_live_tuples + tabentry->n_dead_tuples -
> tabentry->last_anl_tuples;
>
> and deletions surely increase n_dead_tuples.
Yes, but they also decrease n_live_tuples;
anltuples is not affected by deletions.
if (isCommit)
{
tabstat->t_counts.t_new_live_tuples +=
trans->tuples_inserted - trans->tuples_deleted;
tabstat->t_counts.t_new_dead_tuples += trans->tuples_deleted;
}
Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center
ITAGAKI Takahiro wrote: > > Bruce Momjian <bruce@momjian.us> wrote: > > > Patch applied. Thanks. Your documentation changes can be viewed in > > five minutes using links on the developer's page, > > http://www.postgresql.org/developer/testing. > > Thanks. Don't we need to backport it to 8.1 and 8.2? > It was changed at the integration of autovacuum at 8.1. I don't worry about documentation details at that level for non-HEAD releases. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. +