Re: Read Hit Ratio Question- Suggestions Welcome.

From: Jerry Gitomer <jgitomer_at_hbsrx.com>
Date: Thu, 5 Aug 1999 13:58:27 -0400
Message-ID: <7ockcf$31q$1@autumn.news.rcn.net>

Hi Tapan,

    What you are doing is       x = (1 - (a/b) - c)  * 100
    what you want to do is      x = (1 - (a/(b-c))) * 100

regards
Jerry Gitomer

When I used
Tapan Trivedi wrote in message <37A9AFF1.E7098856_at_abbnm.com>...
>Hey Gurus,
> I am doing this query to find out the Read Hit ratios on a
Baseline
>system (upon which further development will be done) .
>
>select 1-(sum(decode(name, 'physical reads', value,0))/
> (sum(decode(name, 'db block gets', value,0)) +
> (sum(decode(name, 'consistent gets', value,0))))) * 100
> "Read Hit Ratio"
>from v$sysstat;
>
> I am getting very weird results on about four systems on which
I have
>run the queries . I am getting NEGATIVE, yes, NEGATIVE results.
What
>does this mean ?
>
> I am getting values like
> -.047
> -18.99
> -2.31
> -.69 etc.
>
> What does this mean ?
>
>
>
> Tapan
Received on Thu Aug 05 1999 - 12:58:27 CDT