Обсуждение: AW: Re: [GENERAL] Vacuum and Transactions

> I also think we have to leave VACUUM alone and come up with a new name
> for our light VACUUM.  That way, people who do VACUUM at night when no
> one is on the system can keep doing that, and just add something to run
> light vacuum periodically during the day.

If I understood what VACUUM light does, I do not think that people
will need to actually do the conventional VACUUM as often anymore.
I understood, that VACUUM light makes outdated tuple heap space available
for reuse, and removes the corresponding index entries.
It does not make space available to other tables or the OS,
but most other DB's do not do that eighter.
The conventional VACUUM would then be something you do as part of a DB 
reorganization (maybe once every month or so).

Andreas

> 
> > I also think we have to leave VACUUM alone and come up with a new name
> > for our light VACUUM.  That way, people who do VACUUM at night when no
> > one is on the system can keep doing that, and just add something to run
> > light vacuum periodically during the day.
> 
> If I understood what VACUUM light does, I do not think that people
> will need to actually do the conventional VACUUM as often anymore.
> I understood, that VACUUM light makes outdated tuple heap space available
> for reuse, and removes the corresponding index entries.
> It does not make space available to other tables or the OS,
> but most other DB's do not do that eighter.
> The conventional VACUUM would then be something you do as part of a DB 
> reorganization (maybe once every month or so).

Yes, but in other DB's if you UPDATE all rows in the table, you don't
double the disk space.  They also reuse DELETEd space automatically.

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