Thomas G. Lockhart wrote:
>
> > >Does it make sense to have a 'row' context which is released just
> > >before starting with a new tuple ? The total number or free is the
> > >same but they are distributed over the query and unused memory should
> > >not accumulate.
> > >I have seen backends growing to 40-60MB with queries which scan a
> > >very large number of rows.
> > I think this would be appropiate.
>
> It seems that the CPU overhead on all queries would increase trying to
> deallocate/reuse memory during the query. There are lots of places in
> the backend where memory is palloc'd and then left lying around after
> use; I had assumed it was sort-of-intentional to avoid having extra
> cleanup overhead during a query.
This problem (introduced in 6.3) is already fixed by Bruce - will be
in 6.3.2
Vadim