Re: testing memory parameters

From: Serge Rielau <>
Date: Mon, 17 Mar 2008 00:09:28 -0400
Message-ID: <>

Ana C. Dent wrote:
> Serge Rielau <> wrote in news:6460opF29k6iqU1

>> Is my reasoning wrong as far as Oracle is concerned? If so where?
>> Cheers
>> Serge

> Obtain any value of BCHR that you deem appropriate.
> 1T4TSHB_enUS209US211&q=oracle+BCHR
> beware a line wrap in URL above

Faszinating. I use similar examples when I teach about how good hit ratio does not mean the application is good. Stuff like (instant doubling of hit ratio for the row): IF EXISTS(SELECT 1 FROM T WHERE pk = 1) THEN   UPDATE T SET c1 = 5 WHERE pk = 1;
END IF; But from an admittedly cursory read I fail to see how this implies that a bad hit ratio can also imply that the application is good?

If it doesn't blink it's no reason to relax. But when it blinks I better pay attention.


PS: Is there similar wisdom on "rows fetched vs. rows read"? Fetched == Rows returned by the cursor
Read = Rows touched to produce the above.

Serge Rielau
DB2 Solutions Development
IBM Toronto Lab
Received on Sun Mar 16 2008 - 23:09:28 CDT

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