Re: Cache Hit Ratio?

>No, slight problem with the formula:
>
>Cache Hit Ratio = (1-(Physical Reads/(db block gets + consistent gets)))
>* 100
>
>BUT...
>In our system, 7x24 shop with lots of reads, the internal counters in
>the V$STATS overflow and go negative, so this formula if fairly useless.
I meant to use the (+) key, but I guess I didn't hit the 'shift' key. The reason I asked, was that the "Oracle Performance Manager" shows that our Cache hit ratio was 75% durring bstat/estat, but when I did the math (according to the book) I got 25%.

Anyways, thank you for the script...we too are a 24/7 shop. I never heard of the internal counter, as you stated...but I'll look into it. Thanks again,
Satar Naghshineh
SatarNag_at_aol.com Received on Tue Aug 19 1997 - 00:00:00 CDT