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cache hit ratio at enterprise manager

537728Mar 19 2007 — edited Mar 19 2007
hit ratio formula is:
(logical_reads - physical_reads/logical_reads )*100

Now, if I open Oracle Enterprise Manager and goes to Instance->Configuration->Memory I can see SGA and PGA configuration. I can also see the cache hit ratio, in my case 35%, but it seems that this is not the formula I mentioned above, because when I execute that formula i get 75% hit ratio:

SELECT 1 -(phy.value / (cur.value + con.value)) "CACHE HIT RATIO"
FROM v$sysstat cur, v$sysstat con, v$sysstat phy
WHERE cur.name = 'db block gets'
AND con.name = 'consistent gets'
AND phy.name = 'physical reads';

CACHE HIT RATIO
---------------
,749500702


So my question is, what is that hit ratio at Oracle Enterprise Manager?
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Locked on Apr 16 2007
Added on Mar 19 2007
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