I ran the following query on my system an notice that the data values for the HIT% is off by 1%. I wonder where each gather their data from? There does not seems to be a consistency? Any idea of why? :confused:
SELECT (consistent_gets + db_block_gets) "LOGICAL_READS",
physical_reads "PHYSICAL READS",
((consistent_gets + db_block_gets) - physical_reads)/
(consistent_gets + db_block_gets) * 100 "Hit Ratio %"
WHERE physical_reads > 0;
column "LOGICAL READS" format 99,999,999,999
column "PHYSICAL READS" format 999,999,999
select a.value + b.value "LOGICAL READS",
c.value "PHYSICAL READS",
100 * ((a.value+b.value)-c.value) /
(a.value+b.value) "BUFFER HIT RATIO"
from v$sysstat a, v$sysstat b, v$sysstat c
a.statistic# = 38
b.statistic# = 39
c.statistic# = 40;