Re: performance question (something to do w/ parameterized

On Mon, 08 May 2006 19:37:37 -0400, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Jeffrey Tenny <jeffrey.tenny@comcast.net> writes:
> > The server was already running with random_page_cost=2 today for all tests, because of
> > the mods I've made to improve other problem queries in the past (my settings noted below, and
> > before in another msg on this topic).
>
> > So to nail this particular query something additional is required (even lower random_page_cost?).
> > What's a good value for slower processors/memory and database in memory?
>
> If you're pretty sure the database will always be RAM-resident, then 1.0
> is the theoretically correct value.

Would it be possible to craft a set of queries on specific data that
could advise a reasonable value for random_page_cost?

What sort of data distribution and query type would be heavily dependant
on random_page_cost?  i.e. randomness of the data, size of the data
compared to physical memory.

klint.

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