Re: random_page_cost configuration parameter

On Wed, Jan 5, 2022 at 07:27:55PM +0100, Mathias Kunter wrote:
> Am 28.12.21 um 17:03 schrieb Tom Lane:
> > Mathias Kunter <mathiaskunter(at)gmail(dot)com> writes:
> > > Consider the situation
> > > where the randomly fetched pages are mostly (or even entirely) cached in
> > > RAM, but where the sequentially fetched pages must be mostly read from
> > > disk. An example for such a scenario is a database system which uses
> > > RAM-cached indices.
> >
> > I think fooling with effective_cache_size is a better way to model
> > that situation.
>
> The default value of effective_cache_size is 4 GB. Which value should be
> used instead on a system which only has 4 GB of total RAM, but still uses
> RAM-cached indices?

This might help:

https://momjian.us/main/blogs/pgblog/2012.html#May_4_2012

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Bruce Momjian <bruce(at)momjian(dot)us> https://momjian.us
EDB https://enterprisedb.com

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