There are various types of recursive activity that could result in log file sync. For example, leaf block splits, and other activity relating to massive restructuring of indexes
Check the session stats for "leaf node splits" and "transaction rollbacks"
Regards
Jonathan Lewis http://www.oracle.com/technology/community/oracle_ace/ace1.html#lewis
The Co-operative Oracle Users' FAQ http://www.jlcomp.demon.co.uk/faq/ind_faq.html
Cost Based Oracle: Fundamentals http://www.jlcomp.demon.co.uk/cbo_book/ind_book.html
On Thu, 12 Oct 2006, Alex Gorbachev wrote:
Maybe I missed something but, perhaps, you are not scoping your data properly in time and/or sessions. If you don't have many XCTENDs than you shouldn't have many log file sync waits either.
You said "once the big chunk of processing starts...". In this case I assume that this chunk is your business critical part you are keen to optimize. Thus, you should limit analysis only to this part.
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