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Re: High current mode buffer gets on insert

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Fri, 14 Mar 2003 11:54:40 -0800
Message-ID: <F001.0056AB29.20030314115440@fatcity.com>

Current mode gets for index inserts is one option. Another cause of CU gets is from checking referential integrity. The block holding the parent key is acquired in current mode as the child row is inserted. There is an optimisation to reduce this effect in arrays/select inserts in Oracle 9, though.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

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> I thought I'd repost to see if I could get a response. Anyone?
>
>
> --- Paul Baumgartel <treegarden_at_yahoo.com> wrote:
> > I'm looking at a client's tkprof output, showing among other
things
> > that the insertion of about 135,000 rows taking 450 seconds of
CPU,
> > and
> > with current mode buffer gets numbering almost 800,000. This is a
> > daily warehouse load process, and I know that indexes are left in
> > place
> > during the load. Am I correct in concluding that the high CPU,
and
> > especially the current mode block gets numbering over 6 times the
> > number of rows inserted, are due to index updates?
> >

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

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Received on Fri Mar 14 2003 - 13:54:40 CST

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