Re: Temp files for simple queries

Default settings might be too low. Try to set work_mem higher. If
operations like sorting don't fit into work_mem, temporary files are used.

Am 22.06.21 um 13:39 schrieb Radoulov, Dimitre:
>
> Hello all,
>
> We have a small Google Cloud SQL PostgreSQL 11 instance.
> The instance is configured with 8G of memory and 4 vCPUs, work_mem is
> 4MB.
>
> I was wondering why the instance uses disk temp files for such a small
> amount of data (see size in the log below)?
>
> I suppose that it's not only the work_mem limit that could trigger
> disk temp file creation or the reported SQL statement is not the only
> one that contributes to it:
>
> I 2021-06-22T09:12:59.164913Z 2021-06-22 09:12:59.163 UTC [1957798]:
> [2-1] db=<db>,user=<user> STATEMENT: SELECT c1, c2 FROM schema1.t1
> WHERE c1 >= $1 ORDER BY c1
> I 2021-06-22T09:12:59.164379Z 2021-06-22 09:12:59.163 UTC [1957798]:
> [1-1] db=<db>,user=<user> LOG: temporary file: path
> "base/pgsql_tmp/pgsql_tmp1957798.0", size 7380992
>
> The t1 table (table and column names have been masked for privacy)
> occupies only  440 kB and has 160 records.
>
>
> Best regards
> Dimitre
>
>
>
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