Re: pgsql: Document random page cost is only 4x seqeuntial, and not 40x.

On Tue, Feb 14, 2012 at 10:44:08PM +0000, Thom Brown wrote:
> On 14 February 2012 21:55, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
> > Document random page cost is only 4x seqeuntial, and not 40x.
> >
> > Branch
> > ------
> > master
> >
> > Details
> > -------
> > http://git.postgresql.org/pg/commitdiff/c1d9df4fa227781b31be44a5a3024865a7f48049
> >
> > Modified Files
> > --------------
> > doc/src/sgml/config.sgml |   20 ++++++++++++++++++++
> > 1 files changed, 20 insertions(+), 0 deletions(-)
>
> This change does say that it is 40 times slower:
>
> "The default value can be thought of as modeling random access as 40
> times slower than sequential..."

I meant to say that it documents why we have a default of 4x, not 40x.
(In fact, real world, it is probably 100x.)

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +