Re: SHMMAX

From: Sybrand Bakker <postbus_at_sybrandb.demon.nl>
Date: Sun, 08 Jan 2006 13:54:32 +0100
Message-ID: <7m22s1d7mqdduunte7ni5maicn1lnvs32v@4ax.com>

On 7 Jan 2006 06:58:05 -0800, "nhk" <chughhk_at_gmail.com> wrote:

>We have 64 bit Hp-ux. RAM on my server is 4gb.If I set SHMMAX to 1 Gb
>and I have 3 databases on the server. What is the limit of SGA for all
>the databases? Is it 1 GB for all or 1 Gb is the limit for one database?

If I recall correctly SHMMAX limits the size of a single shared memory segment. However, shared memory is still paged.

Oracle recommends that the total size of all SGAs on a server shouldn't be bigger than about one third of physical RAM. This is for obvious reasons, because you will force the server to page if you increase the SGAs beyond reasonable limits. That said, you would better tune applications, than trying to get the server on it's knees.

--
Sybrand Bakker, Senior Oracle DBA

Received on Sun Jan 08 2006 - 06:54:32 CST