Re: Data Pump slower than equivalent Export ?!?

"Ronald Rood" <devnull_at_ronr.nl> wrote in message news:0001HW.BF50D8FD021EBD40F0305550_at_news.individual.net...
> On Fri, 16 Sep 2005 16:19:29 +0200, mccmx_at_hotmail.com wrote
> (in article <1126880369.250882.129120_at_z14g2000cwz.googlegroups.com>):
>
>> Oracle 10.1.0.4 EE on RHEL 3
>>
>> Oracle claim that Data Pump is a considerably faster method of loading
>> and unloading data to/from the database.
> <snip>
>> Export takes 43 seconds and Data Pump takes over 3 minutes..!
>>
>> 95% of the delay in Data Pump appears to be in the step:
>>
>> "Estimate in progress using BLOCKS method..."
>>
>> What exactly is done during this step..?
>
> Hi Matt,
> I am quite sure there can be made some improvements in the data pump but
> for
> a serious speed test you need to take a larger database. I just finished
> some
> testing and was quite happy with it. impdp read 46GB of data from a source
> database and stored in a target database in less than 2 hours, over a
> network
> link (100Mb). The ftp session alone of the conventional expdat.dmp (49GB)
> of
> the same database took 1 hour and 20 minutes...
> Disappointing is the fact that only for the data impdp uses parallel
> workers
> and not for the other objects. They are serialized and in my case that
> took
> nearly 10 hours to complete. Conventional exp (full) took 10 hours to
> complete.
> So, I think impdp deserves some more testing ...
>
> Completely missing are warnings about NLS problems. Conventional exp did
> not
> much but it did give warnings ...
>
>
> With kind regards / met vriendelijke groeten,
> Ronald
>
> http://ciber.nl
> http://homepage.mac.com/ik_zelf/oracle
>

Today, I did some tests with Data Pump on AIX 5.2 (Oracle 10.1.0.4). First impressions ? Not so good. Lots of ORA-00600 errors during a full export, or an export of only metadata. I opened a TAR and Oracle is investigating this. And yes, I have read the docs ;-) Other issue : to be able to perform a full export, a user does not only need EXP_FULL_DATABASE, but also CREATE TABLE. Second issue : expdp can't overwrite already existing dump files with the same name ...

The "good old" exp works fine though.

Matthias Hoys Received on Fri Sep 16 2005 - 14:47:42 CDT