You have installed two 64G flash devices to support the Database Smart Flash Cache feature on your database server that is running on Oracle Linux.
You have set the db_smart_flash_file parameter:
DB_FLASH_CACHE_FILE= ‘ /dev/f lash_device_1‘,‘ /dev/f lash_device_2‘
How should the D3_flash_cache_size be configured to use both devices?
A.
Set DB_FLASH_CACHE_SIZE=64G.
B.
Set D3_FLASH_CACHE_SIZE=64G, 64G.
C.
Set D3_FLASK_CACKE_SI2E=i28G.
D.
db_flash_cache_SI2E is automatically configured by the instance at startup.
Explanation:
* Smart Flash Cache concept is not new in Oracle 12C – DB Smart Flash Cache in Oracle 11g.
In this release Oracle has made changes related to both initialization parameters used by DB Smart Flash cache. Now you can define many files|
devices and its sizes for “Database Smart Flash Cache” area. In previous releases only one file|device could be defined.
DB_FLASH_CACHE_FILE = /dev/sda, /dev/sdb, /dev/sdc
DB_FLASH_CACHE_SIZE = 32G, 32G, 64G
So above settings defines 3 devices which will be in use by “DB Smart Flash Cache”
/dev/sda – size 32G
/dev/sdb – size 32G
/dev/sdc – size 64G
New view V$FLASHFILESTAT – it’s used to determine the cumulative latency and read counts of each file|device and compute the average latency