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A Joshi wrote:
>Hi,
> I have a export taken with direct=y. This is done setting a high recordlengh = 64K. When importing using this export sould I set recordlength or buffer? How high is Ok for buffer? I am on 817 on sun 5.8. I need to do this operation frequently and need to tune it.
> Basically is export taken with direct option any different from regular export?
> Or is it better to just use regular export (non direct) with high buffer and use the same buffer for import. thanks for your help.
>
>
>
One of the best tricks, that puts your import in the turbo mode and lets
you import 85 mph in a 55 mph zone
is setting "_disable_logging" to true. Now, this is a dangerous
suggestion and you must make sure that neither
your instance nor machine crashes or you lost the entire database. This
parameter was (ab)used for benchmarks
against the databases that didn't have such protection mechanisms and
were relying on the protection of the underlying
Unix systems instead. Of course, dirty tricks like this were sometimes
applied by equipment resellers. I am aware of
a benchmark in which EISA-based lintel PC has beaten much more powerful
SGI Indigo2 workstation by using this
trick. I know of another member of this list who is aware of the same
benchmark.
Benchmarking tricks aside, this can really speed up your import because
you will eliminate large portion of your I/O.
This suggestion will probably draw some fire, but I will readily take it.
-- Mladen Gogala Oracle DBA Ext. 121 -- http://www.freelists.org/webpage/oracle-lReceived on Mon Jun 06 2005 - 11:45:21 CDT