That's an interesting thought, but why do you
think that only one DBWR process can scan
at a time ?
If you have multiple working data sets,
surely you can have one dbwr process
per working data set doing the scanning.
After all, each working data set has its
own 'range reuse' list (or should that be
the 'object reuse' list for truncate)
Jonathan Lewis
Host to The Co-Operative Oracle Users' FAQ
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Author of:
Practical Oracle 8i: Building Efficient Databases
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-----Original Message-----
To: Multiple recipients of list ORACLE-L <[EMAIL PROTECTED]>
Date: 18 August 2001 14:41
|
|The size of the buffer cache and the number of
|DB_WRITER_PROCESSES has a big impact on the time it
|takes to truncate a table.
|
|Each DBWR process has to scan its portion of the
|buffer cache to flush any blocks belonging to the
|truncated table or its indexes. This is a sequential
|process as only one DBWR process can do this at a
|time.
|
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