Re: init_sequence spill to hash table

On 2013-11-15 12:31:54 +0200, Heikki Linnakangas wrote:
> On 15.11.2013 07:47, David Rowley wrote:
> >On Fri, Nov 15, 2013 at 3:03 AM, Heikki Linnakangas <hlinnakangas(at)vmware(dot)com
> >>wrote
> >>
> >>I think that means that we should just completely replace the list with
> >>the hash table. The difference with a small N is lost in noise, so there's
> >>no point in keeping the list as a fast path for small N. That'll make the
> >>patch somewhat simpler.
> >
> >Attached is a much more simple patch which gets rid of the initial linked
> >list.
>
> Thanks, committed with minor copy-editing. I dialed down the initial size of
> the hash table from 1000 to 16, that ought to be enough.

I am slightly confused by the use of HASH_CONTEXT without setting
ctl->hcxt, that works, but seems more like an accident.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services