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.
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Álvaro Herrera http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
