| From: | Ogden <lists(at)darkstatic(dot)com> |
|---|---|
| To: | Jesper Krogh <jesper(at)krogh(dot)cc> |
| Cc: | Kenneth Marshall <ktm(at)rice(dot)edu>, pgsql-performance(at)postgresql(dot)org |
| Subject: | Re: Query much faster with enable_seqscan=0 |
| Date: | 2010-09-21 19:02:11 |
| Message-ID: | 3062DF4E-7460-4487-818A-BF77F176E501@darkstatic.com |
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| Thread: | |
| Lists: | pgsql-performance |
How odd, I set the following:
seq_page_cost = 1.0
random_page_cost = 2.0
And now the query runs in milliseconds as opposed to 14 seconds. Could this really be the change? I am running ANALYZE now - how often is it recommended to do this?
Thank you
Ogden
On Sep 21, 2010, at 1:51 PM, Jesper Krogh wrote:
> On 2010-09-21 20:21, Ogden wrote:
>> I assume you mean random_page_cost? It is currently set to 4.0 - is it better to increase or decrease this value?
>>
>
> Should be lowered to a bit over seq_page_cost.. and more importantly.. you should
> make sure that you have updated your statistics .. run "ANALYZE";
>
> --
> Jesper
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