Re: Change db block size will improve performance ? ?

Remember that when you change the blocksize, you MUST recreate the Oracle Database from scratch, so your export/import is required.

As to whether performance will improve, is dependent upon the application. In general, a smaller blocksize is recommended for OLTP systems, with the larger blocksize >= 8k is recommended for DW/DSS systems.

One thing to remember as far as SGA is concerned, is that the DB_BLOCK_BUFFERS parameter is specified in Oracle Block Size, so if the Block Size is increased, then the SGA will also increase in Memory requirements. i.e. 1000 Buffers at 2K requires 2Mb, but at 8K requires 8Mb's. However, you will get more data in an 8K block so the number of buffers could be reduced, but probably not bt 1/4.

Rgds
Andrew

agi_at_mail.taicom.com.tw wrote:

> Hi,theres,
>
> My DB is 7.2.3 on Dec Alpha/2000,1 CPU, Physical memory 256MB, with Dec
> UNIX.
>
> I want to increase the db block size from 2k to 8k during the exp/imp
> recently.
>
> I just wonder that increasing the blocksize will/won't improve performance
> ????
>
> Besides,do I need more memory if I change db blocksize ?? more storage for
> importing the original database ??
>
> Thanks in advance for any suggestions !!
>
> Agi
>
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Received on Thu Apr 01 1999 - 05:22:37 CST