| From: | Kenneth Marshall <ktm(at)rice(dot)edu> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | Kevin Grittner <Kevin(dot)Grittner(at)wicourts(dot)gov>, Robert Haas <robertmhaas(at)gmail(dot)com>, Dimitri Fontaine <dim(at)hi-media(dot)com>, "pgsql-hackers(at)postgresql(dot)org" <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: *_collapse_limit, geqo_threshold |
| Date: | 2009-07-08 22:14:16 |
| Message-ID: | 20090708221415.GM22588@it.is.rice.edu |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
On Wed, Jul 08, 2009 at 05:46:02PM -0400, Tom Lane wrote:
> "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov> writes:
> > For a moment it seemed logical to suggest a session GUC for the seed,
> > so if you got a bad plan you could keep rolling the dice until you got
> > one you liked; but my right-brain kept sending shivers down my spine
> > to suggest just how uncomfortable it was with that idea....
>
> If memory serves, we actually had exactly that at some point. But I
> think the reason it got taken out was that it interfered with the
> behavior of the random() function for everything else. We'd have to
> give GEQO its own private random number generator.
>
> regards, tom lane
>
A separate random number generator for GECO make a lot of sense.
Cheers,
Ken
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Robert Haas | 2009-07-09 01:10:20 | Re: *_collapse_limit, geqo_threshold |
| Previous Message | Kasia Tuszynska | 2009-07-08 22:11:09 | modules missing from Application Stack Wizard? |