The root index block problem is more likely to be
the bug fixed in 8.1.7.3 and 9.0.1.3 - the root block
doesn't change much, so shouldn't get many
read consistent copies ever. On trailing blocks on
leaf indexes, it might help - but you have to be careful
that you don't cause the problem to occur 'from the opposite
direction' namely that there are too few CR copies, so
processes keep having to clone a recent block and roll
it back a bit.
--
Jonathan Lewis
http://www.jlcomp.demon.co.uk
Next Seminar - UK, April 3rd - 5th
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Host to The Co-Operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
Author of:
Practical Oracle 8i: Building Efficient Databases
Andrew Mobbs wrote in message ...
>
>Hm... so if your system was suffering cache buffers chains latch
>contention on root index blocks, and you could see many CR copies in x$bh,
>might reducing _max_cr_dba_clone be effective tuning?
>
>I suppose one answer is to Just Do It (not on production, don't panic)
>and see what happens.
>
>--
>Andrew Mobbs - http://www.chiark.greenend.org.uk/~andrewm/
Received on Wed Mar 27 2002 - 12:18:41 CST
