How should the D3_flash_cache_size be configured to use…

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?

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



Leave a Reply 2

Your email address will not be published. Required fields are marked *