Re: Observing Huge Non disk Logical I/O in Glance (small table huge degradation)

Hi,

Try explain plan for this select. Send it to news. And maybe then someone will explain your problem.

Andrew Protasov

> Hi,
>
> We are experiencing a critical performance problem with Oracle.
> Our application is a Pro*C application and Oracle 7.3.3
> We have one function in the application which has the following
> Pro*C code which causes extensive damage to the performance.
>
> EXEC SQL SELECT A_NUMBER FROM INCLUSION_4_GRANULARITY WHERE A_NUMBER =
> :temp;
>
> Commenting out the above said SQL statement gives a performance
> of 250 CDRs / Second. With the above statement the system degrades
> to 65 CDRs / Second. When we observed thru Glance Plus we saw a huge
> number 15000+ in the Non disk Logical Reads and Non disk Logical Writes.
>
> With commented out code the values for the above two are nearly 0.
>
> This is a pointer to the whole problem. If we could avoid this Non disk
> Logical
> read/writes then I belive we will be able to over come the problem.
>
> Can someone give me some pointer to this problem ?
>
> I will also list out the things which I have already tried out
>
> 1. Created the table with "CACHE" option
> 2. Since the table is small table (less than 100 records) I removed
> Index as indexes on small table may be costly.
> 3. We have enough SGA Size (around 181 MB)
>
> --ssuresh
>
>
>
>
Received on Tue Nov 17 1998 - 02:24:46 CST