Re: [HACKERS] wal buffers documentation -errata

I have applied the attached patches to CVS HEAD and 8.2.X to mention
defaults that match the contents of postgresql.conf. I also added a
mention that pg_settings.unit shows the default units for a setting.

One problem is that some settings use a default unit of seconds, but the
default value is one minute, or "1m". shared_buffers has a similar
problem, using 8k blocks as the default unit, but having a default value
of 32MB or similar.

I am unsure how we can really improve this. Saying the default units
are measured in seconds, but the default value is 1 minute is pretty
confusing. Hopefully the pg_settings.unit mention will help, and users
will always use units for fields that have them in postgresql.conf.

I have added lines documenting the memory and time units to
postgresql.conf. Hopefully that will help too.

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

Dave Cramer wrote:
>
> On 11-Jan-07, at 12:49 PM, Tom Lane wrote:
>
> > Dave Cramer <pg(at)fastcrypt(dot)com> writes:
> >> the point is that the documentation suggests that the default is 8
> >> not 8MB, but 8, when in fact the defaults are now given in memory
> >> units not pages
> >
> > Oh, I thought you were complaining that the value was numerically
> > wrong.
> >
> > Perhaps we should convert the documentation to show the defaults in a
> > units-ified way, but if so it needs to be done consistently. Most of
> > the entries seem not to have been changed; for example shared_buffers
> > is still described in blocks.
>
> Yes, everything is described in blocks, but in the configuration file
> everything (I've looked at so far) is specified in memory units.
> While I appreciate the effort that went into making it somewhat
> easier to use memory units I can see this being very confusing for
> the average user.
>
> I would suggest that the documentation needs to be consistent with
> the example configuration file installed by initdb
>
> Dave
> >
> > regards, tom lane
> >
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Bruce Momjian bruce(at)momjian(dot)us
EnterpriseDB http://www.enterprisedb.com

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