public inbox for [email protected]
help / color / mirror / Atom feedFrom: Kouber Saparev <[email protected]>
To: Alvaro Herrera <[email protected]>
Cc: [email protected]
Subject: Re: DELETE takes too much memory
Date: Mon, 4 Jul 2016 20:10:09 +0300
Message-ID: <CAN4RuQt5GZEbkHdPmm=j-z2uE3m3U-USWFNhVRiqYAKv5BZqhg@mail.gmail.com> (raw)
In-Reply-To: <[email protected]>
References: <CAN4RuQtCYxQg0u_NUncLAyLE-Yd9Yv1Ont5R2skJ53Xygvc4Xg@mail.gmail.com>
<[email protected]>
List-Unsubscribe: <mailto:[email protected]?body=unsub%20pgsql-performance>
No. There are AFTER triggers on other tables that write to this one though.
It is an audits table, so I omitted all the foreign keys on purpose.
2016-07-04 20:04 GMT+03:00 Alvaro Herrera <[email protected]>:
> Kouber Saparev wrote:
> > I tried to DELETE about 7 million rows at once, and the query went up to
> > 15% of the RAM (120 GB in total), which pushed some indexes out and the
> > server load went up to 250, so I had to kill the query.
> >
> > The involved table does not have neither foreign keys referring to other
> > tables, nor other tables refer to it. The size of the table itself is 19
> GB
> > (15% of 120 GB). So why the DELETE tried to put the entire table in
> memory,
> > or what did it do to take so much memory?
>
> Are there triggers in the table? Deferred triggers in particular can
> use memory.
>
> --
> Álvaro Herrera http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
>
reply
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: [email protected]
Cc: [email protected], [email protected]
Subject: Re: DELETE takes too much memory
In-Reply-To: <CAN4RuQt5GZEbkHdPmm=j-z2uE3m3U-USWFNhVRiqYAKv5BZqhg@mail.gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox