Re: caching indexes and pages? - Mailing list pgsql-performance

From Kenneth Marshall
Subject Re: caching indexes and pages?
Date
Msg-id 20090122220333.GG1961@it.is.rice.edu
Whole thread Raw
In response to Re: caching indexes and pages?  (Thomas Finneid <tfinneid@fcon.no>)
List pgsql-performance
On Thu, Jan 22, 2009 at 10:58:25PM +0100, Thomas Finneid wrote:
> Thomas Markus wrote:
>
>> try to reorganize your data with CLUSTER and create appropriate indixes
>> (dont forget to check statistics).
>
> One question. Assume I have clustered and new data has been added after
> that, according to the docs that data is added "outside" of the clustered
> data. What happens when I run cluster again? I would assume its smart and
> to only clusteres the new data, i.e. adding it to the already created
> clusters, as apporpriate, so the execution time would be a lot lower,
> right? or would it run through and recluster everything from scratch again?
>
> thomas
>
It reclusters again from scratch. You do get better performance on the
reads from the data that is already clustered.

Cheers,
Ken

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