What is the difference between ASMM and AMM in Oracle?
Answer: Yes, Oracle ASMM and Oracle AMM are for different releases of Oracle: AMM in Oracle 11g: The 11g release uses AMM and manages all of the SGA AND PGA via the memory_target parameter. Also, AMM does not use Linux hugepages.
What is AMM in Oracle 11g?
Automatic Memory Management (AMM) has been available since Oracle version 11, and it does a respectable job of managing the SGA and PGA. When it’s configured, Oracle will manage both the SGA and PGA dynamically, changing pool allocations automatically as memory needs shift.
What is difference between Sga_target and Memory_Target Oracle?
SGA_Target is the size of the SGA not including the PGA. Memory_Target includes both. If the PGA_target + SGA_Target are > Memory_Target, you can get this error.
What is difference between Sga_max_size and Sga_target?
*SGA_TARGET is actual memory in use by the current SGA. This parameter is dynamic and can be increased up to the value of SGA_MAX_SIZE. SGA_MAX_SIZE and SGA_TARGET both are the parameter are used to change the SGA SIZE. *The SGA_MAX_SIZE parameter is the max allowable size to resize the SGA Memory area parameters.
How do I know if my automatic memory management is enabled?
In the Memory Settings section, the Memory Management value is Auto. This indicates that Automatic Memory Management is enabled for the database.
What is Pga_aggregate_limit?
PGA_AGGREGATE_LIMIT specifies a limit on the aggregate PGA memory consumed by the instance. There is no difference in behavior between PGA_AGGREGATE_LIMIT being explicitly set or being set to the default. Actions Taken When PGA_AGGREGATE_LIMIT is Exceeded. Parallel queries will be treated as a unit.
What is DB cache size?
DB_CACHE_SIZE specifies the size of the DEFAULT buffer pool for buffers with the primary block size (the block size defined by the DB_BLOCK_SIZE initialization parameter). The value must be at least 4M * number of cpus * granule size (smaller values are automatically rounded up to this value).
How do I check if AMM is enabled?
memory_target (starting in 11g): If memory_target is set, then AMM is enabled: If memory_target is set to non zero value and : sga_target, sga_max_size and pga_aggregate_target are set to 0, then 60% of memory mentioned in memory_target is allocated to SGA and rest 40% is kept for PGA.
What is Sga_max_size?
SGA_MAX_SIZE specifies the maximum size of the SGA for the lifetime of the instance. On 64-bit platforms and non-Windows 32-bit platforms, when either MEMORY_TARGET or MEMORY_MAX_TARGET is specified, the default value of SGA_MAX_SIZE is set to the larger of the two parameters.
How do I check if automatic memory management is enabled in Oracle 11g?
The Memory Management page appears. In the Memory Settings section, the Memory Management value is Auto. This indicates that Automatic Memory Management is enabled for the database. The initialization parameter values shown on this page are the ones that have been specified in addition to MEMORY_MAX_TARGET .
What is the difference between PGA aggregate limit and Pga_aggregate_target?
PGA_AGGREGATE_TARGET is the parameter for control PGA memory allocation. The actual PGA usage can be as high as three times of the value of PGA_AGGREGATE_TARGET. It will not terminate the session if usage exceeded.
How do I choose a cache size?
Within these hard limits, the factors that determine appropriate cache size include the number of users working on the machine, the size of the files with which they usually work, and (for a memory cache) the number of processes that usually run on the machine.
What is automatic memory management?
Automatic Memory Management. Automatic memory management, also known as automatic garbage collection, is the practice of allowing the language implementation to keep track of used and unused memory, freeing the programmer from this burden.
What is memory management software?
A memory manager is a software utility that operates in conjunction with the operating system. It helps manage memory more efficiently and provides additional features such as flushing out unused segments of memory. All modern operating systems provide memory management.
What is an automatic memory?
Automatic memory management (AMM) is a technique in which an operating system or application automatically manages the allocation and deallocation of memory. This means that a programmer does not have to write code to perform memory management tasks when developing an application.