The following bug has been logged on the website:
Bug reference: 15372
Logged by: Maxim Boguk
Email address: maxim(dot)boguk(at)gmail(dot)com
PostgreSQL version: 9.6.10
Operating system: Linux
Description:
Hi,
pg_stat_statements extension always write pgss_query_texts.stat file into
data_directory/pg_stat_tmp
and ignore stats_temp_directory settings which supposed to overwrite stat
directory location.
It isn't good because this file could be quite a large (and almost always
larger than standard pg_stat_tmp content).
It seems that the issue exists in any supported version of the database.