Re: Oracle v. Postgres 9.0 query performance

Oooo...some bad math there.  Thanks.

On Wed, 2011-06-08 at 12:38 -0700, Samuel Gendler wrote:
>
>
> On Wed, Jun 8, 2011 at 12:03 PM, Tony Capobianco
> <tcapobianco@prospectiv.com> wrote:
>         My current setting is 22G.  According to some documentation, I
>         want to
>         set effective_cache_size to my OS disk cache +
>         shared_buffers.  In this
>         case, I have 4 quad-core processors with 512K cache (8G) and
>         my
>         shared_buffers is 7680M.  Therefore my effective_cache_size
>         should be
>         approximately 16G?  Most of our other etl processes are
>         running fine,
>         however I'm curious if I could see a significant performance
>         boost by
>         reducing the effective_cache_size.
>
>
>
>
>
> disk cache, not CPU memory cache.  It will be some significant
> fraction of total RAM on the host.  Incidentally, 16 * 512K cache =
> 8MB, not 8GB.
>
>
> http://en.wikipedia.org/wiki/CPU_cache
>
>
>
>