Re: [WIP] cache estimates, cache access cost

2011/6/14 Alvaro Herrera <alvherre(at)commandprompt(dot)com>:
> Excerpts from Cédric Villemain's message of mar jun 14 10:29:36 -0400 2011:
>
>> Attached are updated patches without the plugin itself. I've also
>> added the cache_page_cost GUC, this one is not per tablespace, like
>> others page_cost.
>>
>> There are 6 patches:
>>
>> 0001-Add-reloscache-column-to-pg_class.patch
>
> Hmm, do you really need this to be a new column?  Would it work to have
> it be a reloption?

If we can have ALTER TABLE running on heavy workload, why not.
I am bit scared by the effect of such reloption, it focus on HINT
oriented strategy when I would like to allow a dynamic strategy from
the server. This work is not done and may not work, so a reloption is
good at least as a backup (and is more in the idea suggested by Tom
and others)

>
> --
> Álvaro Herrera <alvherre(at)commandprompt(dot)com>
> The PostgreSQL Company - Command Prompt, Inc.
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>

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Cédric Villemain               2ndQuadrant
http://2ndQuadrant.fr/     PostgreSQL : Expertise, Formation et Support