Re: 64k blocks vs 4k blocks

In article <420fsp$1v2_at_pipe3.nyc.pipeline.com>, qmick_at_nyc.pipeline.com (Michael Joseph) writes:
>
> We are experimenting with moving our (almost) read-only data base from a 4K
> block size to a 64K block size.

Are you talking about database blocks OR the block size that your disk device uses?

I didn't think Oracle allowed database blocks larger than 16K in size; except on their soon to be release VLM databases.   

> Tests have shown that on large tables there is a slight gain here but when
> a large table on a 64k volume is joined to a 4k block smaller table there
> is a penalty approaching 100% against performance.
>
> Any other feedback on this would be useful.

There is the DB_File_Multiblock_Read_Count INIT.ORA parameter which can help speed up full table scans.

-- 

Bruce...        pihlab_at_cbr.hhcs.gov.au

*******************************************************************
* Bruce Pihlamae  --  Database Administration                     *
* Commonwealth Department of Human Services and Health            *
* Canberra, ACT, Australia                        (W) 06-289-7056 *
*=================================================================*
* These are my own thoughts and opinions, few that I have.        *
*******************************************************************

"The more complex the argument gets, the easier it is to refute."
"Killing is wrong!"  -- Trent 'The Uncatchable' Castanaveras