Sizing SGA

Hi All,
what is the standard method to resize sga, and what are all the things to be considered. Is there any formulat to do that.
Regards
Venu

There are couple of good notes in metalink. However, there is no any thumb rule for siging SGA. I would recommend you to start with a reasonable value and increase accordingly, if required. It alos depends on whether your db is OLTP or DSS.
Jaffar
null

Similar Messages

Problem in sizing sga

Dear All,
We are using Oracle 10g R2 on windows 2003.Our sga_max_size=2000m and sga_target=800m.We have enabled ASM.
I got an alert message in enterprize manger which says virtual memory paging is happening and its impact is 100%.
Now,Is this problem related to SGA?Do i have to resize my sga_max_size ?
We have 4gb RAM 460 gb hard disk what would be the ideal size for sga?
Regards,
Kris

For guidelines over SGA & memory, refer discussion here...
Re: windows 32bit sga and pga limits
But actual sizing of SGA depends on your application needs. If it needs more SGA, it does. You might need to add more RAM to your server to cope up with existing workload for a given number of users.

Help on 10g 64 bit --Sizing SGA and sysctl.conf

Dear Sir,
I have an oracle10g installed on a 64 bit OS and want to allocate 8GB to SGA and want to confirm if i am using the right settings
My sysctl.conf settings are :
cat /etc/sysctl.conf
# Kernel sysctl configuration file for Red Hat Linux
# For binary values, 0 is disabled, 1 is enabled. See sysctl(8) and
# sysctl.conf(5) for more details.
# Controls IP packet forwarding
net.ipv4.ip_forward = 0
# Controls source route verification
net.ipv4.conf.default.rp_filter = 1
# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0
# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0
# Controls whether core dumps will append the PID to the core filename
# Useful for debugging multi-threaded applications
kernel.core_uses_pid = 1
# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1
# Controls the maximum size of a message, in bytes
kernel.msgmnb = 65536
# Controls the default maxmimum size of a mesage queue
kernel.msgmax = 65536
kernel.shmmax = 8589934592
kernel.shmmni = 4096
kernel.shmall = 2097152
kernel.sem = 3000 32000 100 128
net.core.rmem_default=262144
net.core.rmem_max=262144
net.core.wmem_default=262144
net.core.wmem_max=262144
My init Settings are :
*._DB_BLOCK_LRU_LATCHES=16
*._spin_count=7000
*.archive_lag_target=1800
*.audit_sys_operations=TRUE
*.BACKGROUND_DUMP_DEST='/redf/DB/dbf/dump'
*.circuits=10000
*.COMPATIBLE='10.2.0.4'
*.CONTROL_FILES='/redf/DB/dbf/cntl1/DB_cntl1_01.ctl','/redf/DB/dbf/cntl2/DB_cntl2_02.ctl','/redf/DB/dbf/cntl3/DB_cntl3_03.ctl'
*.CORE_DUMP_DEST='/redf/DB/dbf/dump'
*.cursor_sharing='FORCE'
*.DB_BLOCK_SIZE=8192
*.DB_CACHE_SIZE=1024M
*.db_file_multiblock_read_count=64
*.db_file_name_convert='/redf/DB/dbf','/redf/DB/dbf'
*.DB_NAME='DB'
*.db_writer_processes=8
*.dispatchers='(PROTOCOL=TCP)(DISPATCHERS=10)'
*.FAST_START_MTTR_TARGET=300
*.INSTANCE_NAME='DB'
*.JAVA_POOL_SIZE=64M
*.JOB_QUEUE_PROCESSES=1
*.large_pool_size=150M
*.LOCAL_LISTENER='(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=XX.XX.XX.XXX)(PORT=1521)))'
*.LOG_ARCHIVE_DEST_1='LOCATION=/redf/DB/arch'
*.LOG_ARCHIVE_DEST_2='LOCATION=/orabackup/redf/DB/arch_new'
*.log_archive_dest_state_2='ENABLE'
*.log_archive_format='DB%t_%r_%s.arc'
*.log_archive_max_processes=2
*.log_archive_min_succeed_dest=1
*.LOG_ARCHIVE_START=TRUE
*.log_buffer=50000000
*.MAX_DISPATCHERS=40
*.max_shared_servers=40
*.O7_DICTIONARY_ACCESSIBILITY=FALSE
*.open_cursors=10000
*.optimizer_index_cost_adj=20
*.parallel_adaptive_multi_user=TRUE
*.parallel_automatic_tuning=TRUE
*.parallel_max_servers=20
*.parallel_min_servers=2
*.processes=4000
*.QUERY_REWRITE_ENABLED='TRUE'
*.QUERY_REWRITE_INTEGRITY='ENFORCED'
*.recovery_parallelism=5
*.recyclebin='OFF'
*.remote_archive_enable='TRUE'
*.REMOTE_LOGIN_PASSWORDFILE='EXCLUSIVE'
*.remote_os_authent=FALSE
*.resource_limit=TRUE
*.session_cached_cursors=200
*.sessions=4000
*.SGA_MAX_SIZE=8000M
*.SGA_TARGET=6500M
*.shared_pool_size=1024M
*.shared_servers=10
*.sort_area_size=10485760
*.sql92_security=TRUE
*.standby_archive_dest='/redf/DB/arch'
*.standby_file_management='AUTO'
*.statistics_level='TYPICAL'
*.timed_statistics=TRUE
*.UNDO_MANAGEMENT='AUTO'
*.undo_retention=1800
*.undo_tablespace='UNDOTBS'
*.USER_DUMP_DEST='/redf/DB/dbf/dump'
Want to confirm is this a proper tuend settings as per memory provided ?
I am aware that it also depends on my appication behaviour , but i just want to check whether the above settings would suffice for a 16GB RAM machine and 64 bit oracle10g
Also let me know if any other setttings apart from this are required , i choose to use SGA Target .Further my application is read intensive . Your suggestions will be highly appreciated.
Thanx

Hi,
I suggest you to increase the value kernel.shmmax = 8589934592 of this parameter in sysctl.conf to kernel.shmmax = 1288490188
Later if you want to increase the size of SGA then you need to modify the kernel.shmmax = 8589934592 value. In general practice we keep kernel.shmmax value little greater then the value of SGA.
Refer MOS tech note:
*ORA-27102 Database Will Not Start With SHMMAX Set To 8589934592 (8GB) [ID 461519.1]*
*Linux Big SGA, Large Memory, VLM - White Paper [ID 260152.1]*
thanks,
X A H E E R
Edited by: ora_tech on Dec 26, 2010 10:14 AM

Is properly sized sga?

hello all,
my database size is around 60gb, frequently iam getting performance problems, that job executing not in a time some times 4 hours some times 40 mins like that , when i look for sga and pga i thought parameters not tuned properly iam mentioning all sga & pga parameter here, can anyone tell what could be the best size we can put for every parameter?
to improve performance.
thanks in advance! its urgent.
SQL> show sga
Total System Global Area 629145600 bytes
Fixed Size 2067848 bytes
Variable Size 381682296 bytes
Database Buffers 243269632 bytes
Redo Buffers 2125824 bytes
SQL> show parameter pg
NAME TYPE VALUE
pga_aggregate_target big integer 115762790
SQL> show parameter sort
NAME TYPE VALUE
nls_sort string
sort_area_retained_size integer 0
sort_area_size integer 65536
SQL> show parameter hash
NAME TYPE VALUE
hash_area_size integer 131072
SQL>

SGA_SIZE SGA_SIZE_FACTOR ESTD_DB_TIME ESTD_DB_TIME_FACTOR ESTD_PHYSICAL_READS
552 1 618141 1 48146030
276 .5 1875872 3.0347 130687584
414 .75 697139 1.1278 52267330
1104 2 504218 .8157 39888986
828 1.5 504218 .8157 39888986
966 1.75 504218 .8157 39888986
690 1.25 511079 .8268 39888986

Thump rule for SGA sizing depends on TOTAL DB SIZE

Is there any thump rule for sizing SGA depends on TOTAL database size for OLTP system?

Please dont do that. There was a thumb rule that if you are using oracle >=9i, you can go upto 80% of your physical RAM. But, I will not advice you so.
Start your SGA with an optimal value, keep on eye on your performance, take statspack report and if further increase required in the SGA, go ahed.
Because, setting over size SGA cause problems as well setting below par sga also provide poor performance. It should be sized optimially.
There are few good notes available in metalink.
Jaffar

Getting ORA-27102: out of memory while creating DB using DBCA

Hi All,
I am working on 11.2.0.3 oracle version and linux OS. I am trying to create a new database using dbca and getting error "ORA-27102: out of memory".
Please find the DB version and OS level parameters info below and let me know what i need to do to overcome this issue.
SQL> select * from v$version;
BANNER
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE 11.2.0.3.0 Production
TNS for Linux: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production
$uname -a
Linux greenlantern1a 2.6.18-92.1.17.0.1.el5 #1 SMP Tue Nov 4 17:10:53 EST 2008 x86_64 x86_64 x86_64 GNU/Linux
$cat /etc/sysctl.conf
kernel.shmall = 2097152
kernel.shmmax = 4294967295
kernel.shmmni = 4096
kernel.sem = 250 32000 100 128
net.core.rmem_default = 4194304
net.core.wmem_default = 262144
net.core.rmem_max = 4194304
net.core.wmem_max = 1048576
fs.file-max = 6815744
fs.aio-max-nr = 1048576
net.ipv4.ip_local_port_range = 9000 65500
$free -g
total used free shared buffers cached
Mem: 94 44 49 0 0 31
-/+ buffers/cache: 12 81
Swap: 140 6 133
$ulimit -l
32
$ipcs -lm
------ Shared Memory Limits --------
max number of segments = 4096
max seg size (kbytes) = 4194303
max total shared memory (kbytes) = 8388608
min seg size (bytes) = 1
Please let me know for any other details.
Thanks in advance.

Ok, first, let's set aside the issue of hugepages for a moment. (Personally, IMHO, if you're doing manual memory mangement, and you're not using hugepages, you're doing it wrong.)
Anyhow, looking at your SHM parameters:
kernel.shmall = 2097152
kernel.shmmax = 4294967295
kernel.shmmni = 4096
Let's take those in reverse order:
1.) shmmni - This is the max number of shared memory segments you can have on your system, regardless of the size of each segment.
2.) shmmax - Contrary to popular belief, this is NOT the max amount of shared memory you can allocate system wide! This is the max size, in bytes of a single shared memory segment. You currently have it set to 4GB-1. This is probably fine. Even if you wanted an SGA larger than 4GB, having shmmax set to this wouldn't hurt you. Oracle would simply allocate multiple shared memory segments, until it had allocated enough memory for the SGA. There's really no harm there, unless this parameter is set really low, causing a huge number of tiny shared memory segments to be allocated.
3.) shmall - This is the real shared memory segment limit. This number is the total amount of shared memory you're permitted to allocate, system wide, expressed in pages. Pagesize here is the native OS pagesize, which is 4096 bytes, so, this is 2097152 * 4096 = 8589934592, or, 8GB. So, 8GB is the maximum amount of memory that can currnetly be allocated to shared memory, on your machine.
So, having said all that, you haven't mentioned how many, if any, other Oracle databases are running on the server or their sizes. Secondly, we have no idea what memory sizing parameters you have set on the database that you're trying to create, that's getting the error.
So, if you can provide more details, in terms of how many other databases are already on this server, and their SGA sizes, and the parameters you've chosen for the database that's failing to create, perhaps we can help more.
Finally, if you're not using SGA_TARGET or MEMORY_TARGET, you really need to take the time to configure hugepages. Particularly if you've got a server that has as much memory as you do, and you're planning to have non-trivially sized SGA (10s of GB), then you really want to configure hugepages.
Hope that helps,
-Mark

DB_BUFFER_CACHE is static or not in Oracle10g v.2....?????

Hi ,
I would like you to confirm if the database's buffer size area in SGA is static or dynamic according to the system needs....
I have somehow been blocked as :
SQL> select * from v$sga;
NAME                      VALUE
Fixed Size              1248600
Variable Size         125829800
Database Buffers 159383552
Redo Buffers            7139328In the above sql statement the database buffers are not included in the variable size of the sga.... so can it be assumed that it is a static component ..????
The above values are confirmed (they cannot be otherwise....) in the results of the following statement:
SQL> select * from v$sgainfo;
NAME                                  BYTES RES
Fixed SGA Size                      1248600 No
Redo Buffers                        7139328 No
Buffer Cache Size 159383552 Yes
Shared Pool Size                  109051904 Yes
Large Pool Size                     4194304 Yes
Java Pool Size                     12582912 Yes
Streams Pool Size                         0 Yes
Granule Size                        4194304 No
Maximum SGA Size                  293601280 No
Startup overhead in Shared Pool    37748736 No
Free SGA Memory Available                 0However , there is a table in the Oracle Admininistation e-book which titled "Automatically Sized SGA Components and Corresponding Parameters" and includes , among others , the Buffer Cache component......!!!!!
So , what is true......?????
They seem to be one contrary to the other....!!!!!
Thanks , a lot
Simon

Hi ,
I have just been blocked because in the followng sql statement:
SQL> select * from v$sga;
NAME                      VALUE
Fixed Size              1248600
Variable Size         130024104
Database Buffers      155189248
Redo Buffers            7139328The database buffers is not included in the variable size but in an individual section.....
However , as you have pointed out right executing the statement:
SQL> select * from v$sga_dynamic_components
2 /
COMPONENT                                                        CURRENT_SIZE   MIN_SIZE   MAX_SIZE USER_SPECIFIED_SIZE OPER_COUNT LAST_OPER_TYPE LAST_OPER_MODE LAST_OPER_TIME GRANULE_SIZE
shared pool                                                         113246208 109051904          0                   0          1 GROW           IMMEDIATE      26/03/2007 18:      4194304
large pool                                                            4194304    4194304          0                   0          0 STATIC                                            4194304
java pool                                                            12582912   12582912          0                   0          0 STATIC                                            4194304
streams pool                                                                0          0          0                   0          0 STATIC                                            4194304
DEFAULT buffer cache                                                155189248 155189248          0                   0          1 SHRINK         IMMEDIATE      26/03/2007 18:      4194304
KEEP buffer cache                                                           0          0          0                   0          0 STATIC                                            4194304
RECYCLE buffer cache                                                        0          0          0                   0          0 STATIC                                            4194304
DEFAULT 2K buffer cache                                                     0          0          0                   0          0 STATIC                                            4194304
DEFAULT 4K buffer cache                                                     0          0          0                   0          0 STATIC                                            4194304
DEFAULT 8K buffer cache                                                     0          0          0                   0          0 STATIC                                            4194304
DEFAULT 16K buffer cache                                                    0          0          0                   0          0 STATIC                                            4194304
DEFAULT 32K buffer cache                                                    0          0          0                   0          0 STATIC                                            4194304
ASM Buffer Cache                                                            0          0          0                   0          0 STATIC                                            4194304The database buffers is a dynamic parameter.........if of course the automatic shared memory management is active.....
Thanks,
Simon

SGA_TARGET Doubt

Hi,
We have Oracle 10g database, which have the following parameters.
sga_max_size=1600m
shared_pool_size=704m
So planned to use SGA_TARGET and set the size to 2G.
(ie) sga_target=2G
sga_max_size=2G
Do I have to comment the shared_pool_size=704m ??
Regards,
Mahesh

Chinar wrote:
Aman.... wrote:
So I won't suggest that you remove the shared pool parameter completely. You may reduce the value given to it and start of from a smaller value rather than from the default one granule.
If you want to manage shared memory automatically(by enabling ASMM) there you should be give this to oracle fully automate it.So in general do not need for minimum values for specific automatically sized components.This is also important when investigating performance related problems in future(how application designed?).Hi Chinar
Sometimes your application needs a minimum amount of specific pool as it's written in the documentation:
You can exercise some control over the size of the automatically sized SGA components by specifying minimum values for the parameters corresponding to these components. Doing so can be useful if you know that an application cannot function properly without a minimum amount of memory in specific components. You specify the minimum amount of SGA space for a component by setting a value for its corresponding initialization parameter

Size of oracle.exe

Hi,
I have installed Oracle8i (8.1.7) for NT. I sized SGA to require about 15MB. But when the instance initiates, the oracle.exe process is getting about 30MB of memory! Do you know the reason??
Thanks in advanced,
Carlos

If you are running 32-bit Windows, then it doesn't matter that you've got 8GB physically in the box: that's a common over-configuration. A 32-bit Windows system can only see 4GB of RAM -and only 2GB of that is available to user-mode programs like Oracle.
If you use a /3GB switch, you can let user-mode programs see 3GB instead of 2GB. But that's your lot.
Unless you are also using a /PAE switch, though that has interesting interactions with the /3GB switch and everything else!
Let's assume you're using a bog-standard Windows environment with no odd boot-time switches. That means 2GB is your limit. And that's for everything Oracle might want to use it for: PGA and SGA alike. I don't know how big your PGA needs to be, but assume a worst-case: allow 50% for the PGA, and 50% for the SGA. That means your SGA_MAX_SIZE parameter should be no bigger than 1GB.
For some reason, you say this sort of thing is "not an option". That's fine: but then you live with the massive swapping to disk that will ensue if you don't keep within bounds. Your choice, really.
From memory, LOCK_SGA does indeed work. But if you're locking into memory an over-allocation of SGA, you'll just be making your paging problems worse.

Reconfigure Server Disks

I have an 11.1 database on a HP ProLiant DL380 G5 running windows 2003 SP2. When the server was originally built the drives hosting the the database files and archive logs were configured as RAID 5. Since then my enterprise manager console is filled with ADDM reports about I/O bottlenecks, I/O intensive SQL statements and the like. Queries are taking longer to run and generally speaking people are bummed. These same queries didn't have a problem on the old server that used ASM. Nonetheless, I am not sure what the best approach to reconfiguring the underlying disks is and how to manage the database recovery.
One thought that I had, since this is windows, was to copy the contents of the logical drive, do the reformat and then copy everything back. I think that in theory the database should be fine. But I am both paranoid and afraid of this approach. The contents of the drive are backed up to tape and there is an RMAN backup catalog on a different server.
Given that, what is the best approach to fooling with the underlying disks and not loosing any data?
Regards, Tony

Queries are taking longer to run Be careful about jumping to the conclusion that RAID-5 causes queries to take longer to run. RAID-5 still does striping of reads. It is writes that suffer the penalty.
You must be sure that RAID-5 is the cause of the problem and not something else -- eg inherently inadequate I/O bandwidth (faulty HBA cards have caused misery many a times !), insufficiently sized SGA / FileSystem Cache, concurrency of other I/O bound jobs etc.

Oracle SGA sizing

Hi,
I have an oracle rac 10g with 4 nodes on linux and each node has 12G RAM memory. my current SGA sizing from pfile looks like this, I need suggestions to change values to have better performance...
racdb2.__db_cache_size=2080374784
racdb3.__db_cache_size=2214592512
racdb4.__db_cache_size=5620367360
racdb1.__db_cache_size=2818572288
racdb2.__java_pool_size=16777216
racdb3.__java_pool_size=16777216
racdb1.__java_pool_size=67108864
racdb4.__java_pool_size=67108864
racdb1.__large_pool_size=16777216
racdb2.__large_pool_size=16777216
racdb3.__large_pool_size=16777216
racdb4.__large_pool_size=16777216
racdb2.__shared_pool_size=5737807872
racdb3.__shared_pool_size=5603590144
racdb4.__shared_pool_size=2147483648
racdb1.__shared_pool_size=4932501504
racdb1.__streams_pool_size=16777216
racdb2.__streams_pool_size=0
racdb3.__streams_pool_size=0
racdb4.__streams_pool_size=0

SQL> select * from v$sga_target_advice;
SGA_SIZE SGA_SIZE_FACTOR ESTD_DB_TIME ESTD_DB_TIME_FACTOR ESTD_PHYSICAL_READS
       268           1         471             1            37727
       134          .5       10732          22.7856            54293
       201            .75         498           1.0573            43363
       536           2         435            .9236            29420
       402            1.5         435            .9236            29420
       469           1.75         435            .9236            29420
       335           1.25         442            .9384            31046
7 rows selected.

The SGA was inadequately sized, causing additional I/O or hard parses.

Dear all,
We are using 10g RAC On Solaris 5.10
Very freuently,we are getting the below message in DB Console
The SGA was inadequately sized, causing additional I/O or hard parses.
Additional Information
The value of parameter "sga_target" was "15360 M" during the analysis period.
Under recommendations,
I found that
Increase the size of the SGA by setting the parameter "sga_target" to 30720 M.
Findings Path
Findings Impact (%) Additional Information
The SGA was inadequately sized, causing additional I/O or hard parses. 27 Additional Information
Wait class "User I/O" was consuming significant database time. 13.2
Hard parsing of SQL statements was consuming significant database time. 4.9
Contention for latches related to the shared pool was consuming significant database time. 0.6
Wait class "Concurrency" was consuming significant database time
Can I rely on this info alone and increase SGA.. Is there any other way I confirm this ?.
Dear Seniors,
Please ignore this Thread if you find this question silly..
Please advise
Kai

Hi Kai,
Can I rely on this info alone and increase SGA.. Is there any other way I confirm this ?.Yes. Oracle has specific "cache" advisors to say if your data buffers of shared pool regions are too small.
I have my notes here:
http://www.dba-oracle.com/art_builder_buffers.htm
The besy way to see them is to run a STATSPACK or AWR report . . .
if you find this question silly..It''s not silly at all, it's a VERY common question!
http://www.dba-oracle.com/t_estimating_sga_size.htm
If you are running Oracle on a dedicated server, it's wasteful NOT to allocate all of the RAM to Oracle, less 20% for the OS . . .
Lastly, remember that Oracle has an insatiable appetite for RAM, but there is a point of diminishing marginal return . . .
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

Sizing the SGA

Hi,
I would like to know how to size the initial SGA size while creating the database.
What are the things that we have to consider for sizing the SGA?
If we have to consider if it is OLTP/DSS system, how many concurrent transactions, how many users and all, then provide me a detailed info, like if there are 100 users assign this much space, and so on.
Thank you in advance.
Rajesh

See Rajesh, Tuning is not a rocket science, It can not be learned at the rate of knotes. coming back to your question, you assume your database is going to be used for OLTP, well, even that case, there are number of things still matters.
these are...
1. what would be the size of your database ?
2. No of cuncurrent users conneted to oracle database?
3. What are the physcial resources you have (cpu's, memory etc) ?
4. Amount of sorting peromed by each session.
5 Many more ....
But if you really like to make an educative guess, then you can start with optimal values and increase the size according to demand. Yinguan is already suggested you to go through with tuning guide, which is the basic need for that person like to jump into tuning ocean.
hare krishna
Alok

Error : SGA was inadequately sized, causing additional I/O or hard parses

Friends ,
I got the Following error in my Production server's (Oracle10g with AIX 5.3 platform ) PERFORMANCE ANALYSIS part of OEM :
"The SGA was inadequately sized, causing additional I/O or hard parses." And it shows the Impact result of Database 1.4% .
In present my SGA size is = 9584 MB , And oracle itself recommended to increase it to = 19168 MB (that means twice time of the present value) .
And my total OS Ram size = 32 GB
In this moment , can anybody plz suggest me ,
For increasing the SGA Size , which things(or Database related matters) I need to consider .
OR
Can I face any major problem If I increase the SGA size ?
ORacle version : ORacle 10g
Platform : AIX 5.3 unix server
Number of Database : One
Waiting for ur kind reply .. ...
Edited by: shipon_97 on Oct 19, 2008 6:45 PM

Hi..
>
For increasing the RAM Size , which things(or Database related matters) I need to consider .
OR
Can I face any major problem If I increase the RAM size ?
>
What is the oracle version you are using??
Why do you want to increase the RAM size.Its already 32GB.Why don't you increase the SGA.How many databases are installed on the server.Is there some other applications running on the server.
Anand

Needing to add keep pool to SGA, sizing and checking for room?

Hi all,
I'm needing to experiment with pinning a table and index (recommended by COTS product vendor) to see if it helps performance.
I'm trying to set up a keep pool...and put the objects in it
I've gone into the database, and found that I will need to set up a keep pool:
SQL> show parameter keep
NAME TYPE VALUE
buffer_pool_keep string
control_file_record_keep_time integer 7
db_keep_cache_size big integer 0
That being said, and I'm having a HUGE senior moment right now...how
do I go about making sure I have enough room to make a little keep
pool?
I've looked at my objects I want to put in there, and one is about
.675 MB, and the other is about .370 MB. So, roughly a little more
than 1MB
Looking at my SGA parameters:
SQL> show parameter sga
NAME TYPE VALUE
lock_sga boolean FALSE
pre_page_sga boolean FALSE
sga_max_size big integer 572M
sga_target big integer 572M
Now...how do I find out what is being used in SGA, to make sure I have room?
I've been searching around, and trying to come up with some queries. I
came up with this one:
SQL> select name, value / (1024*1024) size_mb from v$sga;
NAME SIZE_MB
Fixed Size 1.97846222
Variable Size 232.002007
Database Buffers 332
Redo Buffers 6.01953125
From this, it appears everything is being used....so, not sure what to
do from here.
Suggestions and links greatly appreciated!
cayenne

SELECT SIZE_FOR_ESTIMATE, BUFFERS_FOR_ESTIMATE, ESTD_PHYSICAL_READ_FACTOR, ESTD_PHYSICAL_READS
FROM V$DB_CACHE_ADVICE
    WHERE NAME          = 'KEEP'
     AND BLOCK_SIZE    = (SELECT VALUE FROM V$PARAMETER WHERE NAME = 'db_block_size')
     AND ADVICE_STATUS = 'ON';
SELECT   ds.BUFFER_POOL,
         Substr(do.object_name,1,9) object_name,
         ds.blocks                  object_blocks,
         Count(* )                  cached_blocks
FROM     dba_objects do,
         dba_segments ds,
         v$bh v
WHERE    do.data_object_id = v.objd
         AND do.owner = ds.owner (+)
         AND do.object_name = ds.segment_name (+)
         AND do.object_type = ds.segment_type (+)
         AND ds.BUFFER_POOL IN ('KEEP','RECYCLE')
GROUP BY ds.BUFFER_POOL,
         do.object_name,
         ds.blocks
ORDER BY do.object_name,
         ds.BUFFER_POOL; Edited by: sb92075 on Jul 9, 2009 2:48 PM

Sizing SGA

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