Re: Do any of you know?

From: Connor McDonald <mcdonald.connor_at_gmail.com>
Date: Wed, 17 Oct 2012 17:11:08 +0800
Message-ID: <CAB=aETD5gXGa3k5onFZCYpSsYbt_RnxdcB-D1q9OFxS1+zKX=A_at_mail.gmail.com>

For pretty much all kinds of stats now, there is a "rolling invalidation" period that is applied to avoid a parse storm... Look for _optimizer_invalidation_period (or something similar to that).

Cheers
Connor

On Fri, Oct 12, 2012 at 11:05 PM, <Christopher.Taylor2_at_parallon.net> wrote:

> Correct. I know that.
>
> I use dbms_pool.purge to flush the plan information. I wasn't clear on
> that I guess.
>
> Chris
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org]
> On Behalf Of MacGregor, Ian A.
> Sent: Friday, October 12, 2012 9:59 AM
> To: oracle-l_at_freelists.org
> Subject: RE: Do any of you know?
>
> Taking system stats does not invalidate cursors. Statements will
> continue to use the same plans until they are re-parsed for other reasons,
>
> Ian A. MacGregor
> SLAC National Accelerator Laboratory
> Computing Division
>
> ________________________________________
> From: oracle-l-bounce_at_freelists.org [oracle-l-bounce_at_freelists.org] On
> Behalf Of Christopher.Taylor2_at_parallon.net [
> Christopher.Taylor2_at_parallon.net]
> Sent: Friday, October 12, 2012 7:43 AM
> To: jonathan_at_jlcomp.demon.co.uk; mwf_at_rsiz.com; niall.litchfield_at_gmail.com;
> oratune_at_yahoo.com; breitliw_at_centrexcc.com
> Cc: oracle-l_at_freelists.org
> Subject: Do any of you know?
>
> When gathering SYSTEM stats, do those stats take a while to affect the
> query plans once they are collected? (a "while" being some "x" amount of
> time - I thought they would be immediate)
>
> --
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>
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>
>

-- 
Connor McDonald
===========================
blog:   connormcdonald.wordpress.com
web:   http://www.oracledba.co.uk

"If you are not living on the edge, you are taking up too much room."
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Received on Wed Oct 17 2012 - 11:11:08 CEST