| From: | tomas(at)tuxteam(dot)de |
|---|---|
| To: | Robert Haas <robertmhaas(at)gmail(dot)com> |
| Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Josh Berkus <josh(at)agliodbs(dot)com>, Gregory Stark <stark(at)enterprisedb(dot)com>, Greg Smith <gsmith(at)gregsmith(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Simple postgresql.conf wizard |
| Date: | 2008-11-28 07:46:58 |
| Message-ID: | 20081128074658.GA26228@tomas |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
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| Lists: | pgsql-hackers |
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On Thu, Nov 27, 2008 at 05:15:04PM -0500, Robert Haas wrote:
> [...] Maybe
> default_statistics_target should vary with the table size? Something
> like, 0.1% of the rows to a maximum of 100... and then 0.01% of the
> rows after that to some higher maximum.... but always a minimum of at
> least 10. I'm guessing that people with really big tables are less
> likely to mind longer planning times and more likely to benefit from
> finding better plans...
What was the running time of the planner? Quadratic in statistics_target?
Take the square root of table size. Exponential? The logarithm. Or
something like that.
My 1.75 cent
- -- tomás
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