Re: Linux v.s. Mac OS-X Performance

Scott Marlowe <scott.marlowe@gmail.com>

From: "Scott Marlowe" <scott.marlowe@gmail.com>
To: "Sam Mason" <sam@samason.me.uk>
Cc: pgsql-general@postgresql.org
Date: 2007-11-12T17:31:59Z
Lists: pgsql-general
On Nov 12, 2007 11:29 AM, Sam Mason <sam@samason.me.uk> wrote:
> On Mon, Nov 12, 2007 at 10:14:46AM -0700, Steve Wampler wrote:
> > Also, what kernel are you using with CentOS 5 - a 32-bit (with hugemem
> > to support the 8GB) or a 64-bit?  And which was PostgreSQL compiled for?
>
> You don't need a 32bit kernel to support 8GB of memory should you? As
> long as the kernel supports PAE that should be enough to make use of it.
> You only need a 64bit address space when each process wants to see more
> than ~3GB of RAM.

There's a performance hit for using PAE.  Not sure what it is, but I
recall it being the in the 5 to 10% range.