calculate hit ratio using v$buffer_pool_statistics

Hi,

From the manual, the hit ratio for each individual buffer pool would be

SELECT NAME, 1 - (physical_reads / (db_block_gets + consistent_gets) FROM V$BUFFER_POOL_STATISTICS
ORDER BY NAME; With this formula, I would assume that the total of (db_block_gets + consistent_gets) also covers the physical_reads. If not, would it be more correct if the above statement is written as follow:

SELECT NAME, 1 - (physical_reads / (db_block_gets + consistent_gets + physical_reads)
FROM V$BUFFER_POOL_STATISTICS
ORDER BY NAME; I'm a bit confuse with the definition of db_block_gets & consistent_gets. Please do advice. Thank you.

Best Regards,
Jeffrey Yee Received on Wed Jul 30 2003 - 03:52:37 CDT