SGA Size Problem
Hi All,
I want to Know that We Have 8 GB RAM in DATABASE Server 10g R2 and 60 GB database Size and 210 users.
So I want to know what would be the Size of SGA Component and others parameters that affect Performance
pls help me its Urgent
Thanks in advance;
Likasz, using shared server reduces PGA requirements at the cost of increasing SGA requirements. The feature does not save much in the way of total Oracle memory requirements nor was it intended to. The feature exists to reduce the number of Oracle processes that the OS has to support which was an issue on many OS's just a few years ago. It does this at the cost of extra session overhead which is a performance cost compared to using persistent dedicated sessions.
If the front-end is web server or transaction monitor based then you have connection pooling in the front-end and are unlikely to need to basically connection pool on the back-end also. I see no reason to complicate the SGA sizing by configuring an unneeded feature before you have measured the performance of the system using dedicated sessions.
HTH -- Mark D Powell --
Similar Messages
-
dear gurus,
we are using oracle 10g1, with rhas 4e5, where on clients end it is forms 6i with patch 17
now we set in the begining startup time 2048MB SGA size...we found we need to increase more we try to increase from EM web based but give us problem database not shutting down properly and even not starting up.
our physcial RAM is 4GB and swap partition size 16GB
can any one guide me how to increase safely SGA size...as when so many users works it start hanging application...then we have shutdown and startup
thanks and kind regards, any docs in details in linux for sga will be helpfull
salim shahzadas when so many users works it start hanging application...then we have shutdown and startupmay be this is related with some other problem.also check ur hit ratio.because 2 g.b of sga is quite good on 4g.b machine,also check ur others parameters.
whats ur top command show when ur hitting the problem. -
MY RAM IS 12GB HOW WOULD YOU SUGGEST SHMMAX SIZE AND SGA SIZE
Hi Export
MY RAM IS 12GB HOW WOULD YOU SUGGEST SHMMAX SIZE AND SGA SIZE.
thanksafzal wrote:
my ram 12gb
database size 70gb
windows 2003
harddisk 500gbHow large is your SGA now??
Do you have a performance problem yet ??
Is the problem a global problem in the whole database, or are there just some queries that are slow ??
What db version are you using ??
What other applications are using this server ??
How many users are using this database ??
Tuning is very much dependent on the application/situation and database type.
I would like to suggest you start looking at AWR or Statspack.
HTH
FJ Franken
My Blog: http://managingoracle.blogspot.com -
SGA Size for 8.1.7.4 32 bit? , some Interview Questions
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,
Raaj
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?
Answer: Choose one of the answers that apply
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?
Answer: Choose one of the answers that apply
A: approximately 2GB
B: approximately 3.5GB
C: approximately 4GB
D: approximately 8GB
E: approximately 16GB
12) The DBA is about to perform some administrative tasks. Specifying the
OPTIMAL parameter has which of the following appropriate uses?
Answer: Choose one of the answers that apply
A: Limiting concurrent users
B: Limiting concurrent transactions
C: Limiting growth of rollback segments
D: Limiting growth of tables
13) If the DBA wants to find information about how often transactions are
wrapping transaction information between multiple rollback segment
extents, where would the DBA look to find that information?
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?
Answer: Choose one of the answers that apply
A: 50
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);
The DBA attempts to issue the following statement:
ALTER TABLE EMPL
ADD ( PERF_APPRAISE LONG);
What happens?
Answer: Choose one of the answers that apply
A: The statement succeeds.
B: The statement succeeds, but column is added as VARCHAR2.
C: The statement fails.
D: The statement adds a disabled constraint.
16) The primary key of the EMP table has three columns, EMPID, LASTNAME,
and FIRSTNAME. You issue the following SELECT statement:
SELECT * FROM EMP WHERE LASTNAME = 'HARRIS' AND FIRSTNAME = 'BILLI'
AND EMPID = '5069493';
Where would you look to see if this query will use the index associated
with the primary key?
Answer: Choose one of the answers that apply
A: DBA_IND_COLUMNS
B: DBA_TAB_COLUMNS
C: DBA_INDEXES
D: DBA_CLU_COLUMNS
17) You are configuring your index to be stored in a tablespace. Which of the
following storage parameters are not appropriate for indexes?
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
D: Value-based auditing
19) Information in the buffer cache is saved back to disk in each of the
following situations except one. In which situation does this not occur?
Answer: Choose one of the answers that apply
A: When a time-out occurs
B: When a log switch occurs
C: When the shared pool is flushed
D: When a checkpoint occurs
20) In order to allow remote administration of users and tablespaces on an Oracle database, which of the following types of files must exist in the database?
Answer: Choose one of the answers that apply
A: Password file
B: Initialization file
C: Datafile
D: Control file
E: Nothing, SYSDBA privileges are not required for these actions.
21) You are planning the storage requirements for your database. Which of the following is an effect of maintaining a high PCTFREE for a table?
Answer: Choose one of the answers that apply
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: 4421.-
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 -
How to Increase the SGA Size.
Hi Guru's
I want to Know
How to Increase the SGA Size in Database 8.1.7.4.1
My Ram Size is 6 GB
When I query the Below Script
select name, value
from v$parameter
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',
'db_8k_cache_size', 'db_16k_cache_size', 'db_32k_cache_size',
'db_keep_cache_size', 'db_recycle_cache_size', 'large_pool_size');
Result
shared_pool_size 300000000
large_pool_size 0
java_pool_size 50000000
log_buffer 10485760
Please Suggest Me the How Much Value also to increase the SGA
My RAM SIZE is 6 GB
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
First thumb rule is that your SGA should not exceed more than 40% of your PHYSICAL RAM in oracle <= 8i version. You can go around 80% from oracle 9i onwards
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 -
I've got an HP 8750 printer running with a Windows 7 Ultimate machine, and I've got a paper-size problem where it keeps telling me the paper is too big. It's set up for 11 x 17.
The actual wording on the printer is:
Paper installed is larger than needed. Press cancel to replace with correct size, if you wish to save paper, or press check mark to continue.
When you press the check mark it feeds the paper, but for a multi page-document I have to press the check mark for each page to feed.
How do I get it to print 11 x 17 paper without having to press the check mark for each page?''guigs2 [[#answer-672422|said]]''
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# 1) Open up the Firefox Preferences tab. You can do this by typing about:preferences in the URL bar.
# 2) Click "Content"
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# 4) Select "English/United States [en-us]", click "Add"
# 5) re-open "about:accounts"
# 6) Click "Get Started"
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Thank you for replying. Unfortunately, I already did all of these things. As you can see from the below screenshot, the language is already set. Also, this screenshot was taken in Safe Mode, so NoScript is not enabled. About:accounts still says I need to enable cookies for some reason. So, this solution didn't work.... -
I will preface this by saying that this is probably a stupid question. I am pretty much an Oracle newbie, but I'm constantly trying to learn stuff. I have done a lot of reading on this topic, so I definitely have my own opinion, but everybody in my office thinks I'm crazy. So here goes...
We run a data warehouse in my shop on a server that has 6 CPUs and 12 GB of RAM, using Oracle 10.2.0.3. I was perusing our server's settings, and I noticed that the SGA was sized at 528 MB. It was not explicitly set in the parameter file, so I'm guessing that this value is calculated from the underlying pool sizes. Here's my stupid question: Isn't this not a good size for the SGA, given how much RAM we have?
Since we are a data warehouse, we should probably give ourselves a lot of RAM for the PGA's (according to Oracle's documentation). So I would like to crank up the SGA_TARGET to (at least) 4 GB and set the underlying pool sizes to 0 to let Oracle manage it all. But it's the fight of my life in my office. I am convinced that giving the SGA more RAM will increase performance.
So, am I crazy or not?Sam, if everyone else in the office thinks you are crazy then you probably are; however, that does not mean that you are not correct in your argument.
The total amount of memory on the machine is not really a good factor for setting your SGA size. It is a limitation. The SGA size should be set based on the application load. Nevertheless the odds are good that doubling the SGA would have a measurable benefit since your machine has so much spare resource available.
Here is an idea. Take a seriies of statspack snapshots or use the AWR reports to measure the system during normal load. Then bounce the database and double the SGA. Rerun the same load and take the measurement. Compare. You ought to be able to sell this idea. When you see the benefit you can then repeat the procedure a couple of times to get up to a 2G, 3G, or 4G SGA.
Remember that your applicaiton will also need PGA and it is easy for the PGA requirements to equal or exceed the SGA requirements. At some point it may also be necessary to add another database instance (and SGA) to the machine so just because you have the memory does not mean that all of it should be put to immediate use.
HTH -- Mark D Powell -- -
How to decrease SGA size in oracle 9i
hi,
how to decrease SGA size .. now SGA size=400m i want to drecrease to 150m
Thanks,
MohammedWhy do you want to do this? Is your system low on memory?
Perhaps your DB is on a laptop with
only a small amount of memory?
Well an enterprise database server set of
thread inside a complex service would need
a high powered laptop with large amounts
of memory.
Or perhaps your UAT server has 10 databases
on it all competing for resource?The culprit may not be Oracle.
For example (as you have not told us your operating system, windows linux unix?) IBM's AIX unix operating system comes configured optimally for managing file caching in the OS memory; as Oracle also caches the blocks read from disk sometimes the file system caching is redundant and ends up using memory better allocated to Oracle. In that case you tune the Unix kernel to reduce memory allocated to the file system caching. The default settings allow IBM AIX to take up to 80% of system memory for caching bad if you have allocated 40% to the SGA already.........
The really cool thing about AIX is you can do this on the fly and you don't need to reboot so when you go live you juggle until you get an optimal setting and then monitor.
In the end you may just have to add memory. -
How can i increase sga size in oracle 10g
Hello friends
how can i increase my sga size in oracle 10g
Regards
Vicky
Edited by: Vignesh Chinnasamy on 31-Jul-2012 02:28HI
**SQL> Show parameter sga ;**
NAME TYPE VALUE
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 2G
sga_target big integer 2G
**SQL> show parameter memory;**
NAME TYPE VALUE
hi_shared_memory_address integer 0
shared_memory_address integer 0
**[root@mte ~]# ulimit -a**
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
file size (blocks, -f) unlimited
pending signals (-i) 1024
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 1024
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 278528
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
*[root@mte ~]#* -
How to increase SGA size in Oracle 9i release 9.0.1.1.1
Hi,
We have Oracle 2000 server on a intel machine (2.8GHz processor and 2 GB RAM). Virtual memory is :- 3GB.
We have a Oracle 9.0.1.1.1 running on this machine. What are the parameters that I need to set to increase the SGA size. We want a large SGA size with enough space for shared pool.
Thanks in advance.
--MalayMalay,
First Check out the RAM utilization for the OS Kernel and remaining to the applications and then to SGA.
We have Oracle 2000 server on a intel machine (2.8GHz processor and 2 GB RAM). Virtual memory is :- 3GB.I suppose its Windows 2000 Server!!!
& What's the size of the Database?
all these things allow you to decide how "large" you can increase the SGA -
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.
My requirement is that need to get minimum SGA size =10GB for my production system. At present my 11i application server and database running on Red Hat Enterprise Linux AS release 4 (Nahant Update 2) 2.6.9 42.ELsmp (32-bit) system with SGA size of 2GB with multi-node installation. Now we are planning to move from this old server to another set servers for production system with higher capacity.
Basically my requirement is that, for new server minimum SGA size=10GB in 32-bit linux OS, so please help me out to find the right solution.
Version details
RDBMS : 10.2.0.2.0 &
Oracle Applications : 11.5.10.2
thanks,
Ajikumar GHi,
Refer to below link that can help out
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:30011178429375
Reason for refering to link is you can get better information instead of explaning my self - I might miss some thing - just in case.
- Pavan Kumar N
Oracle 9i/10g - OCP
http://oracleinternals.blogspot.com/ -
Hi all,
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
Do you want Database configuration Assistant to Change the Parameter? I gave ignore and I changed the SGA size to: 160, I received the bellow caution
SGA Size can not be greater than maxmimum shared memory segment size (1342177728). Refer to oracle installation guide to configrue your operation system kernel parameters.
Please suggest me on the same....
Thanks
Giruser10737570 wrote:
My other database SGA_MAX_SIZE is 1G.
Now I'm trying to create database using DBCA. By default my sga size allocated is 128MB. It recommends SGA size should be 160MB. I'm not able to extend SGA size. Please refere my previous post...
Could you please tell me why my default screen is showing as 128MB.
ThanksThe oracle installer determines the available sga_size bij calculating free "shared memory"
This is the setting of the maximum shared memory as posted in the first message minus the memory used by your first database, minus some other shared memory stuff.
To overcome this, you have to increase the mamimum shared memory size in your kernel and if needed reboot the system.
If your system happens to be a Redhat Enterprise system, then lookup the variable called
kernel.shmmax = <a certain size>
in /etc/sysctl.conf
Increase that value, and save the file ( as root )
Next run /sbin/sysctl -p to activate the new config -
Reduced SGA_TARGET, but SGA size not changing?
I reduced the sga_taget from 1536M to 512M:
alter system set sga_target = 500M scope = memory;
System altered.
select VERSION from v$instance;
VERSION
10.2.0.3.0
show parameter sga
NAME TYPE VALUE
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 1536M
sga_target big integer 512M
But the real memory still showing the original value
show sga
Total System Global Area 1610612736 bytes
Fixed Size 2030456 bytes
Variable Size 1509950600 bytes
Database Buffers 83886080 bytes
Redo Buffers 14745600 bytes
why is that while it's a dynamic parameter?
Thanks a lot for any help.
Edited by: user10484253 on May 13, 2011 8:36 AM
Edited by: user10484253 on May 13, 2011 8:39 AM
Edited by: user10484253 on May 13, 2011 8:41 AMI would suggest you to check v$sgastat to find out the exact SGA memory you are using currently instead of using "SHOW SGA" when when you set SGA_MAX_SIZE & SGA_TARGET initialization parameters.
Below is a sample output from one of my test dbs. As you can see below my SGA size is only 1GB.
SHOW SGA shows 2GB thats because I have set SGA_MAX_SIZE to 2gb ( which only means that I can grow my sga up till 2 gig , it may not be my current sga size).
you can try increasing or decreasing SGA_TARGET and check memory usage on OS level to see the difference.
SQL>show parameter sga
NAME TYPE VALUE
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 2000M
sga_target big integer 1008M
SQL>show sga
Total System Global Area 2087780352 bytes
Fixed Size 2155336 bytes
Variable Size 1744833720 bytes
Database Buffers 318767104 bytes
Redo Buffers 22024192 bytes
SQL>select name, round(sum(mb),1) mb
2 from (
3 select case when name = 'buffer_cache' then 'db_cache_size'
4 when name = 'log_buffer' then 'log_buffer'
5 else pool
6 end name,
7 bytes/1024/1024 mb
8 from v$sgastat
9 )group by name
10 /
NAME MB
db_cache_size 304
java pool 128
large pool 16
log_buffer 21
shared pool 528
2.1
6 rows selected.
SQL> -- V$SGA_DYNAMIC_FREE_MEMORY: Information about the amount of SGA memory available for future dynamic SGA resize operations.
SQL>select * from V$SGA_DYNAMIC_FREE_MEMORY;
CURRENT_SIZE
1040187392- Krishna -
Hi,
We are in the process to increase the size of SGA to improve the performance of our Production Database, as its performance have been degraded.
Our database server is having total 2GB of RAM.
SGA_MAX_SIZE is not defined in the init.ora file
The following are the details of database memory structures :
Total System Global Area = 180.63088 (MB)
database buffers = 53.4921875 (MB)
shared_pool_size = 100 (MB)
large_pool_size = 0.5859 (MB)
java_pool_size = 20 (MB)
db_block_buffers = 6847 bytes
db_block_size = 8192 bytes
So how much SGA size can we increase to improve the performance of the database server?
which parameters from above are required to be altered and upto how much size ?
Kind request to provide the guidance.
Regards.hi
this depends upon organization to organization
well just check this out the link
http://download.oracle.com/docs/cd/B19306_01/server.102/b14231/create.htm#ADMIN00207
Hope this helps
CHeers -
Hi,
RDBMS : 11.1.0.7.0
OS : RHEL 5 (X86_64)
EBS : 12.1.3
My Database Server RAM size is 128 gb
Currently my Parameters are
SGA_Target = 2g
SGA_max = 2g
Shared_pool_size = 600m
Kernel Parameters are :
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.sem = 256 32000 100 142
kernel.shmmni = 4096
kernel.msgmni = 2878
fs.file-max = 6553600
net.ipv4.ip_local_port_range = 1000 65000
net.core.rmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_default = 262144
net.core.wmem_max = 262144
My question is...
As My project manager is asking to increase the SGA Size as i have 128gb RAM of server.
Maximum how much i can increase the SGA Size
It is PRODUCTION Server... Now it's running with out any issue... but so much RAM is there y can't we use....?
Please advice..
Thanks,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".
The maximum size of a shared memory segment is limited by the size of the available user address space. On 64-bit systems, this is a theoretical 2^64bytes. So the "theoretical limit" for SHMMAX is the amount of physical RAM that you have. However, to actually attempt to use such a value could potentially lead to a situation where no system memory is available for anything else. Therefore a more realistic "physical limit" for SHMMAX would probably be "physical RAM - 2Gb".
In an Oracle RDBMS application, this "physical limit" still leaves inadequate system memory for other necessary functions. Therefore, the common "Oracle maximum" for SHMMAX that you will often see is "1/2 of physical RAM". Many Oracle customers chose a higher fraction, at their discretion.
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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Writing text in 'Tear Away' flyers..
I am composing a flyer with 'tear-away' boxes on the bottom which are vertically sized. How do I 'flip' them over horizontally in order to enter text into these vertical boxes and then place them back in a vertical position to complete the entire fly
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Audigy 2 ZS notebook 24bit sound card
Hi, I would like to use Creative Audigy 2 ZS (PCMCIA slot) 24bit sound card to generate sine, square, noise signals and my Labview version is 5.1 RT. I' m looking for a VI that allows me to use this sound card as variable freq. signal source. Could
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HP Deskjet 3070A: why does it scan only sections of a document?
The printer would only scan sections of an A4 document. I do not semm to have access to ant contyrol panel where I can set the proper scanning area. Why is that? It worked perfectly well a few months ago... Thank you.