- Primary task of smart flash cache is to hold frequently accessed data in flash cache so next time if same data required than physical read can be avoided by reading the data from flash cache.
- Exadata caching mechanism focuses on caching frequently accessed data and index block with performance critical information like control file and file headers.
- Also we can influence caching priorities by using CELL_FLASH_CACHE storage attribute for specific database objects
What will be cached ?
- Frequently accessed data
- Index Block
- File header reads and writes
- Control file reads and writes
- DBA can set the caching priority
What will be not cached?
- Backup related I/O
- Database pump I/O
- Data file formatting
- I/O to mirror copies
- Table scan don't control the cache
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