Oracle-L: Re: 2k and 8k block size

From: <Rajesh.Rao_at_jpmchase.com>
Date: Tue, 11 Feb 2003 07:49:15 -0800
Message-ID: <F001.0054951B.20030211074915@fatcity.com>

The purpose of this feature, I believe, is to accomodate "transportable tablespace" restores, so that it is possible to say,transport a tablespace from a 2K block size database, to a 4k block database.

Raj

                                                                                                                    
                    Michael                                                                                         
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                    io.net>              Subject:     Re: 2k and  8k block size                                     
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                    February 10,                                                                                    
                    2003 04:59 PM                                                                                   
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                    ORACLE-L

Reading my oracle 9i new features , there is now something called: Multiple Database Block Size Support. In other words, it is no longer necessary
to commit to a single block size for your database. I'd suggest looking into this, as
it may now be possible to test using different blocksizes for different tablespaces.

At 01:04 PM 2/10/2003 -0800, Rajesh.Rao_at_jpmchase.com wrote:

     An 8.0.6 ops database being migrated to 9i RAC database on Solaris 8.
     The
     8.0 database had an block size of 2k.  Multiblock read count is 8.
     This is
     an OLTP database, all transactions almost always work on a single row.
     None
     of the row sizes exceed the block size. Hardly any chained or migrated
     rows. Now, during this migration, it was recommended to change the
     block
     size to 8k. And my concerns are:

     1. Would this not increase pinging across the instances? With 9i and
     interconnect and cache fusion, this should be reduced considerably,
     so, is
     it a mute point?
     2. This could alter the execution plans of some statements. Would
     some,
     maybe a very few of the statements not prefer a full table scan?

     Any other positive or negative effects of this increase in block size?

     Thanks
     One Paranoid DBA

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INET: Rajesh.Rao_at_jpmchase.com

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