Re: COPY TO and VACUUM

Hi kevin

first of all thanks for your help. I did a mistake we are using postgres 8.3.

I didn't expect COPY TO frees space but I was wondering Autovacumm delete dead rows as soon as possible, in fact my scenario is:

- Delete all products record for a vendor
- Reload all products record (from new listing) for the same vendor.

Obviously we repeat this process continously and table space is growing really fast.

Can you suggest me an approach for autovacuum within this scenario and, if you want, suggest me an appropriate version of postgres that help solving my problem?

Many thanks in advance again.

BR,
Roberto

----- Messaggio originale -----
Da: "Kevin Grittner" <kgrittn(at)ymail(dot)com>
A: "Roberto Grandi" <roberto(dot)grandi(at)trovaprezzi(dot)it>, pgsql-performance(at)postgresql(dot)org
Inviato: Martedì, 3 settembre 2013 22:34:30
Oggetto: Re: [PERFORM] COPY TO and VACUUM

Roberto Grandi <roberto(dot)grandi(at)trovaprezzi(dot)it> wrote:

> I'm running Postgres 8.4 on Ubuntu 10.4 Linux server (64bit)
> I have a big table tath contains product information: during the
> day we perform a process that import new product continously with
> statemtn COPY TO .. from files to this table.
>
> As result the table disk space is growing fast, it seems that
> postgres is not able to free space for old rows.

COPY TO would not free any space.  Is there some other activity you
haven't yet mentioned?

> Is it possible to run a specific autovacuum acivity or say to
> postgres "every time I delete a row, delete it immedialty and
> don't take care of other transactions" ?

You can configure autovacuum to be more aggressive, or you could
run VACUUM statements.

> Do you have any suggestion for me?

8.4 is getting pretty old; there have been a lot of autovacuum
improvements in recent years.

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company