Conner is right about contention and you can find this out by taking
v$mystat before and after each run. buffer busy wait may also
contribute to the slow response.
ted
Connor McDonald <connor_mcdonald_at_yahoo.com> wrote in message news:<3D25DFF1.34CC_at_yahoo.com>...
> manley wrote:
> >
> > Hi, everyone:
> >
> > I have a strange problem: I have an Oracle 8i database running in W2K server
> > ( only 256M RAM, that's low) with a very large table called Table1 ( about 4
> > millions records). I issued a SQL query at that table in the server machine
> > , like
> > SQL> select col1 from table1 where col1='value1';
> >
> > It takes about 2 minutes or so. But if I open two sessions simultaneously
> > and issue the same query like above , the performance is dynamically
> > dropped, it takes about 20 minutes or more to finish.
> >
> > TIA
>
> You'll want some info from v$session_event, v$mystat and v$sess_io. One
> possible explanation (and there could be many many others) could IO
> contention.
>
> hth
> connor
Received on Sat Jul 06 2002 - 00:27:09 CDT
