Some old thoughts:
https://orastory.wordpress.com/2012/03/09/sql-patch-iii-plus-parallel-baselines/
Sent from my iPhone
On 3 Aug 2018, at 21:16, Rich J
<rjoralist3@xxxxxxxxxxxxxxxxxxxxx<mailto:rjoralist3@xxxxxxxxxxxxxxxxxxxxx>>
wrote:
Hey all,
In 11.2.0.3 I have a vendor-supplied SQL that needs temporary band-aiding. I'd
like to have it run as a PQ, but don't want it to run with the default DOP of
32 for this instance. Enter SPM baselines.
I've identified the SQL ID and loaded it into SPM from cursor cache. I then
artificially set PARALLEL_DEGREE_LIMIT to "4" for a different session, ran the
SQL with a PARALLEL hint, and confirmed the parallel limit via V$PQ_SESSSTAT.
I then loaded that plan into SPM, altered the original baseline to use it and
set that plan to "fixed".
I then verified the original statement in a new session uses only 4 PQ slaves,
again by using V$PQ_SESSSTAT. Yay, it works!
However, is this specifically documented anywhere? I couldn't find any docs
where it stated a plan's DOP was retained in an SPM baseline or if it could be
overridden by session settings.
Thoughts?
TIA,
Rich