Re: Oracle Myths- Tablespace placement answered by Oracle

In article <3ce510a9$0$15144$afc38c87_at_news.optusnet.com.au>, Nuno says...
>
>In article <ac2ufu$mcjir$1_at_ID-114862.news.dfncis.de>, you said (and I
>quote):
>>
>> The only reliable benchmark is how it runs on your system.
>
>Yupper.
>
>
>> Even without concurrency in the strictest sense it is still beneficial to
>> put the indexes and data on different disks. The above info relates to one
>> query. There is nothing to stop multiple queries against the same rows and
>> indexes from processing concurrently.
>>
>> So yes, you can get performance benefit by splitting the data and indexes
>> onto different disks."
>>
>
>
>call me a dreamer, but if you put tables and indexes in same tablespace
>and spread that tablespace over a number of devices you get EXACTLY the
>same result as above.

you might even find you get BETTER ;)

the goal -- even IO distribution.

puttting indexes on disk1 and data on disk2 -- you may well find your index (much more cacheable in general then the data) results in very very little physical IO to disk 1. Disk 2 on the other hand it getting beat up.

stripe disk1 and disk2 and you'll get even io in this simple case.

>
>;-D
>
>--
>Cheers
>Nuno Souto
>nsouto_at_optushome.com.au.nospam

--
Thomas Kyte (tkyte@oracle.com)             http://asktom.oracle.com/ 
Expert one on one Oracle, programming techniques and solutions for Oracle.
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