I am running the following (Oracle suggested - 8i) query to get the biffer hit ratio. This is our production Apps database. The numbers for logical and physical reads seem VERY high (especially phys_reads, which obviously causes our hit ratio to drop to 0). What could have caused this?
SQL> list 1 select A.value + B.value "logical_reads", 2 C.value "phys_reads", 3 D.value "phy_writes", 4 (A.value+B.value)-C.value "log_minus_phys", 5 round(100 * ((A.value+B.value)-C.value) / (A.value+B.value)) 6 "Buffer Hit Ratio" 7 from V$SYSSTAT A, V$SYSSTAT B, V$SYSSTAT C, V$SYSSTAT D 8 where A.statistic# = 38 9 AND B.statistic# = 39 10 AND C.statistic# = 40 11* AND D.statistic# = 44 SQL> / logical_reads phys_reads phy_writes log_minus_phys Buffer Hit Ratio ---------------------------- ---------------------------- ---------------- ---------------- ---------------- 18,446,744,070,414,253,130 18,446,744,069,433,707,559 2,043,488 980,545,571 0 Here are some other stats; DTSTAMP PHYSICAL_READS DB_BLOCK_GETS CONSISTENT_GETS PHYSICAL_WRITES -------------------- ---------------------------- ---------------- ---------------------------- --------------- PHYSICAL_READS_DIRECT PHYSICAL_WRITES_DIRECT SESSION_LOGICAL_READS ---------------------------- ---------------------- --------------------- 08-APR-2002 10:35:16 18,446,744,069,434,437,169 171,781,916 18,446,744,070,280,471,598 2,103,859 18,446,744,047,946,114,866 966,679 1,032,014,671 -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Glenn Travis INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).