Re: Oracle DB performance tuning training
- From: Stéphane Faroult <sfaroult@xxxxxxxxxxxx>
- To: contact@xxxxxxxx, sethmiller.sm@xxxxxxxxx
- Date: Sat, 22 Aug 2015 07:41:56 -0500
From my field experience with clients - they usually take the following from
such a class:
1) End user complains about performance
2) Look at top wait events in graphical representation in EM or top section in
AWR in this time window
3) Analzye and reduce it with the mentioned and trained tools
4) Result = Happy end user
... and we all know that this does not work out well in an effective way
(otherwise we would be jobless). A lot of work time in organizations is
wasted on tuning wait event <X> without any notice to the complaining end
users, just because of some tools show some high colorful graphs :-)
If I may add my $0.02, what Stefan describes looks horribly familiar to
me, and what I have also seen is meetings where the DBA was all talking
about wait events, and the developers at the same table had no clues
1) about what he was talking about
2) about how "wait events" could relate to their own code
I have vivid remembrances of the faces of developers when an ebullient
DBA was talking to them about a "buffer busy" problem. Even when
explained what it means, they couldn't see how it related to their code.
Which means that even "tuning wait event <X>" is often only possible
through what I call the "magical parameter dance", changing that more or
less obscure parameter that will bring a 5% improvement that no end user
will notice.
One of the problems of performance classes is that (I know it's bad for
business) their goal should not be to give attendees a list of buttons
to push, but to enable them to educate their own developers and
evangelize them. All the more as people who are sent to (often
expensive) classes are relatively experienced and senior people in an
organization, and aren't the ones that code. If they don't get the
global picture and aren't able to explain it to others, it's a waste of
time and money (networking aside). When after the course they make
developers understand why what Hibernate does behind the scene is bad
and how THEY (developers) could change it, then there is hope.
Stéphane Faroult
--
//www.freelists.org/webpage/oracle-l
Other related posts:
