Hardware sizing for Oracle Database and Oracle Oracle E-Business Suite Applications - New Implementation

Hardware sizing for Oracle : Customer, hardware vendor and the consulting patner should work together to find the correct estimates.

Initial Sizing of database hardware (RAM,CPU,DISK,NETWORK) is a not easy task,
As we Donot have a set of calculations which can help in sizing our Oracle database and ERP.

Complete understanding of the Data and type of users is really helpful (Number of named users ,Number of concurrent Users
Number of Concurrent Manager (CM) Process etc )
Assume network as the important components.
Database Size should be based on benchmarks and collective experience of Oracle, H/W vendor and knowledge gained from existing customers.

If we have and Existing hardware and database/E-biz running on it ,There are ways to monitor the hardware utilizations but Sizing/Hardware recommandation in the beginig in difficul.

Memory is one of the KEY component as far as Oracle database is concerned.



Lets start with SGA.
Asummption 50Gb database.
When you say show SGA , You will get an output like this.

SQL> show sga (an EXAMPLE)
Total System Global Area 629145600 bytes
Fixed Size 2074896 bytes
Variable Size 369100528 bytes
Database Buffers 251658240 bytes
Redo Buffers 6311936 bytes

Total System Global Area
- Total size in bytes

Fixed Size
- Contains general information about the state of the database and the
instance, which the background processes need to access.
- This area is usually less than 100k in size.

Variable Size
- This section is influenced by the following init.ora parameters
shared_pool_size
large_pool_size
java_pool_size

Database Buffers
Holds copies of data blocks read from datafiles.
size = db_block_buffers * block size

Redo Buffers
A circular buffer in the SGA that holds information about changes made to the database.
Enforced mininum is set to 4 times the maximum database block size for the host operating system.

SGA components:

Data buffer cache - cache data and index blocks for faster access
Shared pool - cache parsed SQL and PL/SQL statements.
Redo Log Buffer - committed transactions that are not yet written to the redo log files.
JAVA pool - caching parsed Java programs.
Streams pool - cache Oracle Streams objects.
Large pool - used for backups, UGAs, etc


I tried to put some data together based on experience. It does not invlove any recommandations from oracle.
This is just for the study purpose,Please be advised to get in touch with oracle for any official recommandation.

PLEASE NOTE THAT THESE ARE JUST TEST DATA based on experience.

Database block buffer sizing.

DBsize/30 to DBSIZE/80
Assuming that 50GB database , Should have SGA ,Somewhere between 1.7 GB to 700 MB
It will depend on the type of database (OLTP or Discision support system)


Shared Pool.:

15% of Database block Buffer. (Approximate)
50GB database : 1GB Database Block Buffer : 150mb Shared Pool.
50GB database, Shared pool size between 80 MB to 160m
You may start with less and keep incresing later.


REDO LOG BUFFER

Memory within the SGA for buffering redo information prior to being written to the redo log files.
10-30m.(For 50gb Database)
Enforced mininum is set to 4 times the maximum database block size for the host operating system



The PGA consists of three components:
Stack Area
Data Area
Sort Area.



PGA sizing : 196608 + 1M (OS overhead) =1.1M to 2m * number of concurrent user (Max) should be the PGA value.

11g PGA:

If SGA_TARGET, SGA_MAX_SIZE and PGA_AGGREGATE_TARGET are set to 0,
60% of memory mentioned in MEMORY_TARGET is allocated to SGA and rest 40% is kept for PGA.

AMM manages all SGA and PGA memory together,
shift memory from SGA to PGAs and vice versa.
You only need to set a MEMORY_TARGET (and if you like, MEMORY_MAX_TARGET parameter).



Now you can have the SGA=80% of RAM (10-20% for OS) , If Shared Server configuration.
SGA=50% of the RAM if dedicated server process.



DISK SPACE:

Please check your database size and try to find out the expected growth of the database,





There are so many Sizing Questionnaire available from Different vendors. I am summarizing few of them here.


IBM hardware sizing for Oracle database and oracle Oracle E-Business Suite Applications - New Implementation
questionire:
http://www-03.ibm.com/support/techdocs/atsmastr.nsf/WebIndex/PRS1672


Oracle_eBusiness_Suite_Sizing_Questionnaire:

http://www9.unisys.com/eprise/main/admin/corporate/doc/Oracle_eBusiness_Suite_Sizing_Questionnaire_V3.doc



DELL , Oracle E-Business Suite questionire:
http://i.dell.com/sites/content/shared-content/solutions/en/Documents/erp-sizing.doc


IBM Sizing Questionnaire for
Oracle Business Intelligence Enterprise Edition (OBIEE)
http://www.oracle.co.jp/appsweb/oacc/ibm/TMP/Oracle%20Business%20Intelligence%20Sizing%20Questionnaire%20v3.1.12_JP20080520.doc



From Oracle Support: login required:
Oracle Applications Release 12 Upgrade Sizing and Best Practices [ID 399362.1]


Not a free one : But available:
http://www.rampant-books.com/download_sizing_spreadsheets.htm


For Oracle-SUN hardware:
http://www.oracle.com/us/products/servers-storage/ref-guide-066235.pdf