From: Ron <ronljohnsonjr@gmail.com>
To: pgsql-admin@lists.postgresql.org <pgsql-admin@lists.postgresql.org>
Subject: Re: How can i be certain autovacuum is causing reuse if table still grows
Date: Tue, 28 Jul 2020 00:15:54 -0500
Message-ID: <2500ca1c-312e-c495-ad98-1b593d030c71@gmail.com> (raw)
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> All lines even old ones might be updated by our application.
Ah. Even so, there are benefits to maintaining "lots of smaller chunks"
instead of One Giant Table: "pg_dump --jobs=X" will run faster, for example,
when there are more small-to-mid-sized tables instead of A Few Giant
Tables. Ditto "reindexdb --jobs=X".
Given that even "old" records get updated, I'd look into some other key that
you can "naturally" partition on.
On 7/27/20 10:54 PM, Sidney Aloisio Ferreira Pryor wrote:
> Thank you Ron.
> Yes there is a column id in which value is provided by a sequence.
>
> But it was not clear to me exactly how to partition?
> The idea is to cover a limited range of "id" so there will be less lines
> to vacuum on each operation?
>
> Because yet we will need eventually to vacuum all others.
> All lines even old ones might be updated by our application.
>
> ----------------------------------------------------------------------------
> *De:* Ron <ronljohnsonjr@gmail.com>
> *Enviado:* terça-feira, 28 de julho de 2020 00:39
> *Para:* pgsql-admin@lists.postgresql.org <pgsql-admin@lists.postgresql.org>
> *Assunto:* Re: How can i be certain autovacuum is causing reuse if table
> still grows
> On 7/27/20 5:19 PM, Keith Fiske wrote:
> [snip]
> > Also, I would not recommend partitioning simply to improve vacuuming.
> > Especially if extensive tuning hasn't been tried first. Most times you can
> > get per-table tuning working well enough to get autovacuum running
> > properly. Especially on 9.6 and even more-so on PG11, where autovacuum has
> > itself been improved.
>
> SIMPLY to improve vacuum performance? No. But there are reasons that
> partitioning was "invented", and minimizing the work needed to be done on
> the whole of a Very Large and Rapidly Growing table is one of them.
>
> --
> Angular momentum makes the world go 'round.
>
>
--
Angular momentum makes the world go 'round.
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Subject: Re: How can i be certain autovacuum is causing reuse if table still grows
In-Reply-To: <2500ca1c-312e-c495-ad98-1b593d030c71@gmail.com>
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