Re: Using OPTIMIZER_CAPTURE_SQL_PLAN_BASELINES=TRUE in Production
- From: Marcin Przepiorowski <pioro1@xxxxxxxxx>
- To: Chris Dunscombe <cdunscombe@xxxxxxxxx>
- Date: Mon, 8 Oct 2012 16:39:09 +0100
On Mon, Oct 8, 2012 at 2:00 PM, Chris Dunscombe <cdunscombe@xxxxxxxxx>wrote:
> Hi Marcin,
>
> The reason for using plan stability is ensure predictable performance, we
> have experienced a number of instances where execution plans have "flipped"
> from good to bad and caused a number of significant issues. The "plan" is
> to use SPBs to prevent these issues from happening.
>
>
Looks like problems with bind variable peeking - again if you have problem
with couple of SQL you can think about SPB
if you have problems with all probably you should find other solution. Did
you try to disable bind peeking or get rid of histograms on all columns and
gather histograms only for columns with skew data distribution ?
Like Michael mentioned in his mail - first plan captured will be accepted
until you run evolve - keep this in mind when you implement your solution.
--
Marcin Przepiorowski
http://oracleprof.blogspot.com
--
//www.freelists.org/webpage/oracle-l
Other related posts:
