Responsibilities of buffer manager in dbms
- Handles all requests for database blocks.
- Reads data from disk pages (hard disk) into main memory (RAM) whenever needed.
- If the data already exist in main memory, then buffer manager passes the address in main memory to the requestor.
- If not, then fetch the data from hard disk to main memory and pass the address in memory to the requestor.
- It decides which data to be cached in main memory.
- Replacement strategy – to create room for new data blocks from disk pages
- Pinned blocks – to recover database from crashes
- Forced output of blocks – to write forcefully back to disk as required