Herwig Goemans <herwig(dot)goemans(at)gmail(dot)com> writes:
> I think I have to get a stacktrace of the postgres server process , not
> of psql but I do not how to do that.
Right. The wiki page I pointed you to upthread has recipes for that.
https://wiki.postgresql.org/wiki/Generating_a_stack_trace_of_a_PostgreSQL_backend
regards, tom lane