Visit the Below Website to access unlimited exam questions for all IT vendors and Get Oracle Certifications for FREE
http://www.free-online-exams.com
http://www.free-online-exams.com
Problem Description: oradism process is not running
oradism file permission is as below
-r-sr-s--- 1 oracle dba oradism
not -rwsr-xr-x root dba oradism
grep -i dism /etc/security/exec_attr
returns nothing.
Explanation:
The use of DISM requires that the ora_dism process starts. The process will not start unless SGA_MAX_SIZE is greater than sum total of all SGA components.
This means that in case you use SGA_TARGET. you specify size of SGA_MAX_SIZE greater than SGA_TARGET
Please refer Doc ID 778777.1(When Will DISM Start On Oracle Database)
Please check the below parameter is enabled
_use_ism= TRUE
select a.ksppinm "Parameter",
b.ksppstvl "Session Value",
c.ksppstvl "Instance Value",
a.KSPPDESC "Describtion"
from x$ksppi a, x$ksppcv b, x$ksppsv c
where a.indx = b.indx and a.indx = c.indx
and a.ksppinm like '_use_ism';
Dynamic intimate shared memory (DISM) is a unique feature of Solaris. It achieves dynamic memory management. On other OSs, When you specify SGA_MAX_SIZE, then the complete size of SGA_MAX_SIZE is reserved from your memory (reserved from Swap not from physical RAM) at instance startup. Then you can dynamically increase SGA_TARGET size until you reach SGA_MAX_SIZE. On Solaris, however, and due to DISM feature, SGA_MAX_SIZE is not reserved from the memory at instance startup but it is allocated when needed. This presents a great value since you do not reserve memory you are not using.
If DISM is not used then SGA_MAX_SIZE is reserved from your memory (reserved from Swap not from physical RAM).
By default, SGA_MAX_SIZE is not set during database installation and hence it takes the same value as SGA_TARGET. The use of SGA_TARGET is not a necessity to use DISM. Oracle will use DISM instead of ISM if SGA_MAX_SIZE is set larger than the total of the database buffers (in particular, db_cache_size dynamic SGA resizing is not supported with the older db_block_buffers parameter), the shared pool, the redo buffers, the large pool, the Java pool, the fixed size. In this case you will need to check the total of following parameters:
* db_cache_size
* java_pool_size
* large_pool_size
* log_buffer
* shared_pool_size
* streams_pool_size
* db_keep_cache_size
* db_recycle_cache_size
The difference between the total and the SGA_MAX_SIZE is so small that it can be approximated in calculations related to Granule size, so DISM should not be started, otherwise the ora_dism process will be started. .
Use of DISM does not depend on whether you use pfile or spfile.You can use DISM with pfile.
References:
notes 1205673.1 and 1018855.1
oradism file permission is as below
-r-sr-s--- 1 oracle dba oradism
not -rwsr-xr-x root dba oradism
grep -i dism /etc/security/exec_attr
returns nothing.
Explanation:
The use of DISM requires that the ora_dism process starts. The process will not start unless SGA_MAX_SIZE is greater than sum total of all SGA components.
This means that in case you use SGA_TARGET. you specify size of SGA_MAX_SIZE greater than SGA_TARGET
Please refer Doc ID 778777.1(When Will DISM Start On Oracle Database)
Please check the below parameter is enabled
_use_ism= TRUE
select a.ksppinm "Parameter",
b.ksppstvl "Session Value",
c.ksppstvl "Instance Value",
a.KSPPDESC "Describtion"
from x$ksppi a, x$ksppcv b, x$ksppsv c
where a.indx = b.indx and a.indx = c.indx
and a.ksppinm like '_use_ism';
Dynamic intimate shared memory (DISM) is a unique feature of Solaris. It achieves dynamic memory management. On other OSs, When you specify SGA_MAX_SIZE, then the complete size of SGA_MAX_SIZE is reserved from your memory (reserved from Swap not from physical RAM) at instance startup. Then you can dynamically increase SGA_TARGET size until you reach SGA_MAX_SIZE. On Solaris, however, and due to DISM feature, SGA_MAX_SIZE is not reserved from the memory at instance startup but it is allocated when needed. This presents a great value since you do not reserve memory you are not using.
If DISM is not used then SGA_MAX_SIZE is reserved from your memory (reserved from Swap not from physical RAM).
By default, SGA_MAX_SIZE is not set during database installation and hence it takes the same value as SGA_TARGET. The use of SGA_TARGET is not a necessity to use DISM. Oracle will use DISM instead of ISM if SGA_MAX_SIZE is set larger than the total of the database buffers (in particular, db_cache_size dynamic SGA resizing is not supported with the older db_block_buffers parameter), the shared pool, the redo buffers, the large pool, the Java pool, the fixed size. In this case you will need to check the total of following parameters:
* db_cache_size
* java_pool_size
* large_pool_size
* log_buffer
* shared_pool_size
* streams_pool_size
* db_keep_cache_size
* db_recycle_cache_size
The difference between the total and the SGA_MAX_SIZE is so small that it can be approximated in calculations related to Granule size, so DISM should not be started, otherwise the ora_dism process will be started. .
Use of DISM does not depend on whether you use pfile or spfile.You can use DISM with pfile.
References:
notes 1205673.1 and 1018855.1
No comments:
Post a Comment