Although the subject line reads buffer advisor, I was commenting on the suggestion in the thread that using CURSOR_SHARING=FORCE might be a useful tactic to deal with the tendency of the shared pool to grow even when SQL isn't going to be reusable. I specifically wasn't commenting on the buffer advisor because I can't recall the last time I used it. Some examples of what I mean't now I'm not on a train. SPM - SQLBASELINES (SPM) NOT WORKING WITH CURSOR_SHARING=FORCE AND ORDER BY XMLDB - WRONG RESULTS WITH EXISTSNODE AND CURSOR_SHARING=FORCE DB LINK - ORA-00979 REPORTED USING GROUP BY TO_CHAR AND CURSOR_SHARING=FORCE Pro*Cobol - CURSOR_SHARING=FORCE CAUSES QUERIES TO FAIL WITH ORA-907 these all affect "current" versions. Over the years I've just seen too many issues as a side effect of CURSOR_SHARING=FORCE to be happy with it other than as a temporary fix. On Fri, Sep 12, 2014 at 8:14 AM, Jonathan Lewis <jonathan@xxxxxxxxxxxxxxxxxx > wrote: > > I think the biggest problem with the buffer advisor is that it's > reporting stats since the instance started up, NOT for the interval. A > piece of advice that "on average" looks okay for the instance might be bad > for the critical period you're examining. I am also a little suspicious > about how smart the advisor can be regarding tablescans and "small tables" > - for example, if you increase the buffer then a large table can become a > medium table (without changing size) and end up being buffered more > aggressively than you'd like, kicking more useful data out of the cache. > > > Regards > Jonathan Lewis > http://jonathanlewis.wordpress.com > @jloracle > ------------------------------ > *From:* oracle-l-bounce@xxxxxxxxxxxxx [oracle-l-bounce@xxxxxxxxxxxxx] on > behalf of Niall Litchfield [niall.litchfield@xxxxxxxxx] > *Sent:* 12 September 2014 08:01 > *To:* andrew.kerber@xxxxxxxxx > *Cc:* ORACLE-L; Mark Powell; Mark W. Farnham > *Subject:* Re: buffer advisor > > The feature also has a long, long history of not playing nicely with > other Oracle features. A search of the MOS bug database will reveal a > number of reasons that might preclude it in your environment. > > -- Niall Litchfield Oracle DBA http://www.orawin.info