Re: Slow statement using parallelism after 9.6>11 upgrade

"Arnaud L." <arnaud.listes@codata.eu> writes:
> We have upgraded our database from 9.6 to 11 (and updated PostGIS from 
> 2.3 to 2.5 as well).
> ...

Have you re-ANALYZEd the database?  The problem with this query
seems to be the spectacularly awful rowcount estimate here:

>    ->  Bitmap Index Scan on planet_osm_ways_nodes_idx 
> (cost=0.00..11190.36 rows=1420982 width=0) (actual time=0.268..0.268 
> rows=1 loops=1)
>          Index Cond: (nodes && '{1}'::bigint[])

The planner should be able to do better than that, given up-to-date
statistics on the "nodes" column.

            regards, tom lane