I want SGA size=4GB when RAM size=8GB.

Hello,
If i am not wrong, oracle takes the 40% of RAM size by default for SGA. At one of my clients site server, they have 8 GB RAM , now i wanted to a lot them at least 3GB to 4GB RAM for SGA. As i tried to do so , it was not taking more than 2GB ...
Why oracle does not take SGA size more than 2GB ? how can this be increased ? can someone please put some light on this point.
ORACLE 10G R2
Windows Server 2005
Thanks and Regards,

Hello,
In Windows *32 bit* you are limited to *2GB* per process (whatever the process). So the Process oracle.exe
cannot overcome this limit except if you use the */3GB* parameter.
So if you want to have a larger SGA you should think to migrate to a *64 Bit* OS. But keep in mind that having
large SGA is not the only way of tuning a database.
Please find enclosed a link about this topic:
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:707585800346136316
Hope this help.
Best regards,
Jean-Valentin
Edited by: Lubiez Jean-Valentin on Mar 26, 2010 10:04 PM

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Hi Export
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afzal wrote:
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harddisk 500gbHow large is your SGA now??
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HTH
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My Blog: http://managingoracle.blogspot.com

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1.-
2.c
3.a
4.a
5.c
6.b
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8.d
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10.a -
11.a
12.c
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14.d
15.c
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How to Increase the SGA Size.

Hi Guru's
I want to Know
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When I query the Below Script
select name, value
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where name in ('shared_pool_size', 'java_pool_size', 'streams_pool_size',
'log_buffer', 'db_cache_size', 'db_2k_cache_size', 'db_4k_cache_size',
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Regards
***SBJ***

SGA size on 8i is static , and for increasing the size you have to make the changes in the pfile and bounce the database
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http://mohamedazar.wordpress.com/2010/08/30/can-i-increase-sga-target-size-greater-than-sga-max-size/
Edited by: Amigo on Dec 18, 2010 1:31 AM

ORACLE SGA size

We bought a server for oracle data warehousing which has got 200GB RAM. Can I set set my SGA_TARGET to 100GB. Is it true the more SGA size result in better performance.
Thaks
jeevan

Hi Jeevan,
I would not set sga_target, it can cause RAM thrashing . . .
In an article titled Automatic Shared Memory Management we see:
http://www.oracle.com/technology/pub/articles/10gdba/week17_10gdba.html
Some pools in SGA are not subject to dynamic resizing, and must be specified explicitly. Notable among them are the buffer pools for nonstandard block sizes and the non-default ones for KEEP or RECYCLE. If your database has a block size of 8K, and you want to configure 2K, 4K, 16K, and 32K block-size pools, you must set them manually.
Their sizes will remain constant; they will not shrink or expand based on load. You should consider this factor when using multiple-size buffer, KEEP, and RECYCLE pools.
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On a dedicated server, your goal is to allocate all the RAM, without causing swapping. I have my notes here:
http://www.dba-oracle.com/art_dbazine_ram.htm
Hope this helps . . .
Donald K. Burleson
Oracle Press author
Author of "Oracle Tuning: The Definitive Reference"
http://www.rampant-books.com/book_2005_1_awr_proactive_tuning.htm

Max SGA size in 32bit OS

Hi,
I have a EBS Production Instance (12.1.1) in a 32-bit OS (RHEL4.0).
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Our sga size is 1.7GB
Is there any way to increase our SGA size.
Please advice.
Thanks in advance.

You can use BIG PAGES
For more info you can read the below docs:
http://www.oracle-base.com/articles/linux/LargeSGAOnLinux.php
32-bit Architecture and the hugemem Kernel
The RHEL 3/4 smp kernel can be used on systems with up to 16 GB of RAM. The hugemem kernel is required in order to use all the memory on systems that have more than 16GB of RAM up to 64GB. However, I recommend the hugemem kernel even on systems that have 8GB of RAM or more due to the potential issue of "low memory" starvation (see next section) that can happen on database systems with 8 GB of RAM. The stability you get with the hugemem kernel on larger systems outperforms the performance overhead of address space switching.
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HTH -- Mark D Powell --

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How to increase SGA size in Oracle 9i release 9.0.1.1.1

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We have Oracle 2000 server on a intel machine (2.8GHz processor and 2 GB RAM). Virtual memory is :- 3GB.
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Thanks in advance.
--Malay

Malay,
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When I try to create a database using DBCA, My default SGA Size : 128. PGA:794. When I click Next button, I receive the following caution...
Following parameters do not meet the recommended minimum size requirements:
An SGA size of atleast 160MB is recommended
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Thanks
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user10737570 wrote:
My other database SGA_MAX_SIZE is 1G.
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shipon_97,
Your understanding is wrong. From your previous posts it appears you never read the concepts manual.
Begging on my knees PLEASE READ IT and stop asking doc questions.
Sybrand Bakker
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