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How to increase performance in parrallel unload

 
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kalaikala

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Joined: 21 Jul 2007
Posts: 27
Location: Chennai

PostPosted: Wed Apr 30, 2008 5:06 pm    Post subject: How to increase performance in parrallel unload
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A table has huge number of data. I want to unload it in a file.

In the table unload I am getting CPU time as 6 mins and Clock time 30 mins. To get better performance I planned to do parallel unload.

Select * from XXXXXXXX.YYYY

When I do parallel unload for all partitions in the tablespace CPU time is so high(~15 mins) and Clock time (3 mins) only.

TEMPLATE UNLDDS DSN &USERID..SMPLUNLD.&TS..T&PART.
UNIT SYSDA DISP (NEW,CATLG,CATLG) SPACE (5000,500) TRK
UNLOAD TABLESPACE DBXXXXX.TSMYYYY
UNLDDN UNLDDS
FROM TABLE XXXXXXX.YYYY

I want to improve its performance(by reducing both CPU and Clock). Please help me out in this.
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enrico-sorichetti

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Joined: 14 Mar 2007
Posts: 10327
Location: italy

PostPosted: Wed Apr 30, 2008 5:14 pm    Post subject: Reply to: How to increase performance in parrallel unload
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Quote:
Please help me out in this.


we cannot do it...
most of the time optimizing elapsed has negative effects on the CPU utilization

( parallelism, buffering, .... )
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kalaikala

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Joined: 21 Jul 2007
Posts: 27
Location: Chennai

PostPosted: Wed Apr 30, 2008 5:18 pm    Post subject:
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So the table unload will be better than the tablespace unload. Because its performance is good in CPU and Clock time too.

Am i correct?.
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