Maximum SGA size in 32-bit OS

Hi All
I want to deploy Oracle Linux 5 to set up for DBA and the server and OS is 32-bit. My questions are
what is the maximum limit of SHMMAX value i can set?
and for this what is the maximum size of oracle SGA?
looking for your early response.
Jeesun

My questions are what is the maximum limit of SHMMAX value i can set?
and for this what is the maximum size of oracle SGA?It depends on if you are using PAE or not.
More at:
http://en.wikipedia.org/wiki/Physical_Address_Extension
http://www.puschitz.com/TuningLinuxForOracle.shtml
http://www.idevelopment.info/data/Oracle/DBA_tips/Linux/LINUX_8.shtml

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How much can go for SGA size in 32-bit Linux OS for 11i

Dear all,
I am looking for a better solution to my doubt from all the Guru's.
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Version details
RDBMS : 10.2.0.2.0 &
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thanks,
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Hi,
Refer to below link that can help out
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:30011178429375
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- Pavan Kumar N
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http://oracleinternals.blogspot.com/

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Dear all,
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Hi all,
Is there a metalink note or oracle list of the SGA size limits on the different platforms and 32/64bit?

Not sure that there is such documents on My Oracle Support. However TECH: Unix Semaphores and Shared Memory Explained (Doc ID 15566.1) explains how Oracle is using Unix/Linux shared memory segments.
Generally speaking I would say that maximum sga size is not an Oracle limit but an OS limit: on Unix it depends on SHMxxx kernel parameters and on Windows I don't know as Oracle architecture is quite different from Unix (a single but multithreaded process using "normal" memory).
See also: Oracle® Database Administrator's Reference 11g Release 2 (11.2) for Linux and UNIX-Based Operating Systems
for AIX and Solaris:
http://download.oracle.com/docs/cd/E11882_01/server.112/e10839/tuning.htm#BABBDBDE
http://download.oracle.com/docs/cd/E11882_01/server.112/e10839/appe_sol.htm#UNXAR344
Edited by: P. Forstmann on 20 mai 2011 11:52

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Hi buddies,
I got some interview questions, might be simple for geeks in DBA. I am in need of answers. Could anyone help me.
Thanks,
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1) Does windows NT support direct I/O?
Answer: Choose one of the answers that apply
A: No, only AIO
B: Yes, depending on hardware.
C: Yes.
D: No.
2) Can you take a coldbackup from solaris and use it on windows NT?
Answer: Choose one of the answers that apply
A: Yes.
B: Yes if RMAN backup performed from NT server.
C: Yes, after running RMAN convert.
D: No.
3) All of the following will alter the number of checkpoints that occur in one hour on the database, except one. Which is it?
Answer: Choose one of the answers that apply
A: Decreasing tablespace size
B: Decreasing size of redo log members
C: Setting LOG_CHECKPOINT_INTERVAL greater than the size of the redo log file
D: Setting LOG_CHECKPOINT_TIMEOUT to zero
4) The DBA is attempting to back up the Oracle database control file. After
issuing the ALTER DATABASE BACKUP CONTROLFILE TO TRACE command, where can the DBA find the backup control file creation materials Oracle created for him or her ?
Answer: Choose one of the answers that apply
A: USER_DUMP_DEST
B: LOG_ARCHIVE_DEST
C: CORE_DUMP_DEST
D: BACKGROUND_DUMP_DEST
5) What is the most important action a DBA must perform after changing the database from NOARCHIVELOG TO ARCHIVELOG?
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A: Shutdown normal and restart the database
B: Perform a full logical database backup
C: Perform a full offline database backup
D: Manually switch the log files
6) Which of the following choices lists an ALTER USER option that can be executed by the user herself or himself?
Answer: Choose one of the answers that apply
A: DEFAULT TABLESPACE
B: IDENTIFIED BY
C: TEMPORARY TABLESPACE
D: PROFILE
7) You need to view the initialization parameter settings for your Oracle
database. Which of the following choices does not identify a method
you can use to obtain values set for your initialization parameters?
Answer: Choose one of the answers that apply
A: Issue SELECT * FROM DBA_PARAMETERS; from SQL*Plus
B: Issue SELECT * FROM V$PARAMETER; from SQL*Plus
C: Issue SHOW PARAMETERS from Server Manager
D: Use OEM Instance Manager
8) As a result of a media failure, the current online redo log group is corrupted, the database crashes, as the current online group is inaccessible. Which type of incomplete recovery are you most likely to perform ?
Answer: Choose one of the answers that apply
A: Change-based
B: Time-based
C: Recovery using a backup control file
D: Cancel-based
9) User SNOW executes the following statement: SELECT * FROM EMP. This
statement executes successfully, and SNOW can see the output. Table
EMP is owned by user REED. What object would be required in order for
this scenario to happen ?
Answer: Choose one of the answers that apply
A: User SNOW would need the role to view table EMP.
B: User SNOW would need the privileges to view table EMP.
C: User SNOW would need a synonym for table EMP.
D: User SNOW would need the password for table EMP.
10) Which one of the following statements is true?
Answer: Choose one of the answers that apply
A: The request queue is common, and the response queue is different for all the dispatchers.
B: The request queue and response queue are different for all the dispatchers.
C: The request queue is different, and response queue is common for all the dispatchers.
D: The request queue and response queue are common for all the dispatchers.
11) What is the largest SGA size for 8.1.7.4 32 bit?
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B: approximately 3.5GB
C: approximately 4GB
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C: Limiting growth of rollback segments
D: Limiting growth of tables
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wrapping transaction information between multiple rollback segment
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Answer: Choose one of the answers that apply
A: DBA_ROLLBACK_SEGS
B: V$ROLLSTAT
C: V$ROLLNAME
D: DBA_SEGMENTS
14) You have 30 rollback segments in your database, for which
TRANSACTIONS_PER_ ROLLBACK_SEGMENT is set to 49 and
TRANSACTIONS is set to 1000. During periods of heavy usage, about how many rollback segments will be actively used by Oracle?
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B: 60
C: 20
D: 30
15) The DBA has a table created with the following statement:
CREATE TABLE EMPL
(EMPID NUMBER(10),
LASTNAME VARCHAR2(40),
RESUME LONG RAW);
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ALTER TABLE EMPL
ADD ( PERF_APPRAISE LONG);
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B: The statement succeeds, but column is added as VARCHAR2.
C: The statement fails.
D: The statement adds a disabled constraint.
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and FIRSTNAME. You issue the following SELECT statement:
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AND EMPID = '5069493';
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A: DBA_IND_COLUMNS
B: DBA_TAB_COLUMNS
C: DBA_INDEXES
D: DBA_CLU_COLUMNS
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Answer: Choose one of the answers that apply
A: OPTIMAL
B: INITIAL
C: PCTINCREASE
D: NEXT
18) You need to set up auditing in an order entry and product shipment
application so that when the ORDER_STATUS column in the ORDERS
table changes to SHIPPED, a record is placed in a special table associated
with a part of the application that gives sales representatives a daily list
of customers to call on a follow-up to make sure the customer is satisfied
with the order. Which of the following choices represents the best way
to perform this auditing?
Answer: Choose one of the answers that apply
A: Statement auditing
B: Object auditing
C: Audit by access
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19) Information in the buffer cache is saved back to disk in each of the
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A: When a time-out occurs
B: When a log switch occurs
C: When the shared pool is flushed
D: When a checkpoint occurs
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A: Password file
B: Initialization file
C: Datafile
D: Control file
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A: Oracle will manage filling data blocks with new records more actively.
B: Oracle will manage filling data blocks with new records less actively.
C: Oracle will leave more space free in data blocks for existing records.
D: Oracle will leave less space free in data blocks for existing records.
22) You manage database access privileges with roles where possible.
You have granted the SELECT_MY_TABLE role to another role, called
EMP_DEVELOPER. To view information about other roles that may be
granted to EMP_DEVELOPER, which of the following dictionary views
are appropriate?
Answer: Choose one of the answers that apply
A: DBA_ROLE_PRIVS
B: DBA_TAB_PRIVS
C: USER_SYS_PRIVS
D: ROLE_ROLE_PRIVS
23) In order to set your SQL*Plus session so that your NLS_DATE_FORMAT
information is altered in a specific way every time you log into Oracle,
what method would be used?
Answer: Choose one of the answers that apply
A: Setting preferences in the appropriate menu option
B: Creating an appropriate LOGIN.SQL file
C: Issuing the ALTER USER statement
D: Issuing the ALTER TABLE statement
24) You create a sequence with the following statement:
CREATE SEQUENCE MY_SEQ
START WITH 394
INCREMENT BY 12
NOMINVALUE
NOMAXVALUE
NOCACHE
NOCYCLE;
Two users have already issued SQL statements to obtain NEXTVAL, and
four more have issued SQL statements to obtain CURRVAL. If you issue a
SQL statement to obtain the NEXTVAL, what will Oracle return?
Answer: Choose one of the answers that apply
A: 406
B: 418
C: 430
D: 442

1.-
2.c
3.a
4.a
5.c
6.b
7.a
8.d
9.b
10.a -
11.a
12.c
13.b
14.d
15.c
16.a -
17.a
18.d
19.c
20.a
21. -
22.d
23.b
24.?
hope it helps u.
Thanks
Kuljeet

Oracle 8.1.7.4 32 bit and SGA size

hi gurus,
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Oracle: 8.1.7.4 32 bit
i have seen documents saying that maximum SGA allocation possible is only 1.75 GB due to 32 bit application limitation.
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any option like /AWE in windows?
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charles

OS : solaris 5.8 64 bit
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Ronny Egner
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Need to Increase SGA Size

Hi,
RDBMS : 11.1.0.7.0
OS : RHEL 5 (X86_64)
EBS : 12.1.3
My Database Server RAM size is 128 gb
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kernel.msgmax = 65536
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As My project manager is asking to increase the SGA Size as i have 128gb RAM of server.
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As per the Note
Maximum SHMMAX values for Linux x86 and x86-64 [ID 567506.1]
=======================================================================
QUESTION 2
===========
What is the maximum value of SHMMAX for a 64-bit (x86-64) Linux system?
ANSWER 2
===========
Oracle Global Customer Support officially recommends a " maximum" for SHMMAX of "1/2 of physical RAM".
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Occasionally, Customers may erroneously think that that setting the SHMMAX as recommended in this NOTE limits the total SGA. That is not true. Setting the SHMMAX as recommended only causes a few more âshared memory segmentsâ to be used for whatever total SGA that you subsequently configure in Oracle. For additional detail, please see Document 15566.1, "SGA, SHMMAX, Semaphores and Shared Memory Explained"
==========================================================================
Our server RAM is 128 gb.... as per the note 1/2 of the physical RAM we can assign for SHMMAX parameter... (apprx 60gb)
How can i understood this answer for my configuration......
Please advice...
Thanks,

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Does java have a formal maximum file size for java.io.File?
Somewhere along the way here where I work we started assuming it was 2GB, is that accurate?
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Do 64-bit JDKs support larger files?
Does the max file size depend on JDK vendor?
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In all cases, I believe, the file size limits are imposed by the underlying operating system, and the value varies (by system and os version).
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Database creation - SGA size

Hi all,
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Following parameters do not meet the recommended minimum size requirements:
An SGA size of atleast 160MB is recommended
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user10737570 wrote:
My other database SGA_MAX_SIZE is 1G.
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You can use BIG PAGES
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http://www.oracle-base.com/articles/linux/LargeSGAOnLinux.php
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Above article taken from http://www.puschitz.com/TuningLinuxForOracle.shtml#32BitArchitectureEdited by: user00726 on Aug 6, 2010 2:02 AM

Heap Size in 64 bit operating systems

Hi,
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Please let me know how to get more heap size under 64 bit OS?
Regards,
-Suresh Shirgave

From a cmd window run a simple program using a 64-bit jvm (HelloWorld or similar) with different -Xmx values to establish the limit at which the program will run.
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Maximum SGA size in 32-bit OS

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