topic Re: Oracle - Additional memory not able to be used in Operating System - HP-UX

Oracle - Additional memory not able to be used

Dennis Flinn — Fri, 04 Aug 2006 12:46:52 GMT

We have a Proliant 380 server on which Oracle V9.2 is running. When the server was first installed and the database was created the system had 2 GB of memory. Recently the memory was upgraded to 4 GB of memory; however, if a change is made to a memory parameter (i.e. db_cache_size) an ORA-00384 Insufficient Memory to Grow Cache is generated. For example the size of db_cache_size before the memory upgrade was 1048576000; after the increase to 4 GB and no additional applications or databases were installed on the system setting db_cache_size to 1048576001 causes the ORA-00348 error. The additional memory can be seen on the system using the System Properties. This system is Widows2003 server and I haven't work a great deal with this combination of Oracle and Windows - so I'm at a loss to determine why the Oracle can't take advantage of the additional memory.

Thanks,
Dennis

Re: Oracle - Additional memory not able to be used

A. Clay Stephenson — Fri, 04 Aug 2006 12:50:35 GMT

You are posting in the wrong Forum. This is for databases running under HP-UX; however, I suspect that if you switch from that extremely advanced, trouble-free, secure operating system that you are currently running to a more primitive, archaic, plague prone OS such as HP-UX, your problems might go away.

Re: Oracle - Additional memory not able to be used

Julio Yamawaki — Fri, 04 Aug 2006 22:26:01 GMT

Hi,

Which command are you using to grow cache size?
Are you trying to do this online?
If you are trying to do this withou stopping/starting database, this parameter is limited by SGA_MAX_SIZE.

Regards,

Re: Oracle - Additional memory not able to be used

Hein van den Heuvel — Fri, 04 Aug 2006 22:58:30 GMT

This is a VIRTUAL memory limitation.
The real fix is running 64-bit on a Unix box using large pages. :-)

Your best bet is probably to boot with the /3GB modifier.

Alternatively you can have Windoze + Oracle do teh adress extention bit and look at a big SGA through windows in low address space.

Check out pages like:
http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx

Google for Oracle, Windows, SGA, 3GB and such for more info.

Enjoy,
Hien.

Re: Oracle - Additional memory not able to be used

Yogeeraj_1 — Sat, 05 Aug 2006 01:05:23 GMT

Hi Dennis,

Again, this is an Operating system issue - Windows 2003. Unless you specify that there is more than 2GB RAM during bootup, the additional 2GB cannot be used.

The /3GB and /PAE switches in the Boot.ini file is normally used.

The /3GB switch functionality lets device-driver developers test their drivers in this configuration without having to install one of the Windows Server 2003 products just listed. The user-mode memory space is now limited to 3 GB.

The /PAE switch lets developers perform similar testing of device drivers by forwarding 64-bit addresses to kernel-mode components. This feature is known as Physical Address Extension (PAE), and it may not work on all chip sets. Any addresses that are over 32 bits are guaranteed to work by using the /nolowmem switch from the Boot.ini file that discards the lower 4 GB of memory.

Caution: Also note that the /3GB switch can cause some applications to have problems that are related to address dependencies or to a reduction in kernel space.

see the microsoft site for more information on how to configure your system
http://support.microsoft.com/kb/291988/

kind regards
yogeeraj

Re: Oracle - Additional memory not able to be used

Dennis Flinn — Mon, 07 Aug 2006 14:12:12 GMT

First, I simply saw the forum topic and posted the question. Also, I forgot to say that the additional memory was recognized the by system my apology for leaving that out. But, Julio answer about the SGA_MAX_SIZE was the issue. Thanks again for the responses.

Clay:

Sometimes we donâ t get to chose and decisions are made for us, but if I were really look for that primitive, archaic, and plague prone OS then I might take VMS over all!

Re: Oracle - Additional memory not able to be used

Dennis Flinn — Mon, 07 Aug 2006 14:17:36 GMT

I forgot to close the thread on my last message.

Dennis