Wow Michael you are absolutely right. Turning jit off results in a query
execution about twice as fast as pg11. That is a huge relief. I will read
the jit related docs and see if there is anything smarter I should be doing
other than disabling jit entirely, but it works a treat for this query.
>
> Does anyone have a theory of why pg15 should behave so differently to pg11
> here? Better still, any suggestions for configuration that might make pg15
> behave more like pg10. I am really dreading the prospect of stepping our
> many live implementations back to pg11 :-(.
>
One major factor
Hello
We have an application (https://dhis2.org) which has been using postgresql
as a backend for the past 15 years or so. Gradually moving through pg
versions 8,9,10 etc as the years went by. At the moment a large number of
our implementations are using versions 13, 14 and 15. Unfortunately we
