On Wed, 11 Mar 2020 at 08:59, Torsten Krah <krah.tm@gmail.com> wrote:
Hi,
I am building a docker image with a postgresql 12.2 instance and while doing so and importing a dump and running some update scripts wal size is increasing.
When finished I don't need all those wal files anymore and tried to force the daemon to clean them up and tried this:
select pg_switch_wal(); CHECKPOINT;
and did wait for a minute.
Sometimes it works and wal files are cleaned and moved away so my image size is way smaller - but it does not happen always in that minute.
So is there a way to tell postgres to force the housekeeping of the wal stuff via a statement / command line tool? In a "normal" running instance it just takes care of itself and it will happen sooner or later and it doesn't really matter when that will happen - but with my docker image which is automatically build it would be nice to have a deterministic way of trigger that to reduce the final size image.
The size of the task varies, so sometimes takes longer than 60s, depending upon your hardware.