OS Block Size

[nac]

Hi everyone,

We are planning for a large OLTP database. When issues has been analyzed there is a serious discussion on changing the SUN OS default block size 512k to 2k (or) 4k.

We know INIT parmeter setings for oracle will do for the db_block_size. And it should be in multiples of OS Blocks

But we would like to know whether changing of OS default block size is recommended or not. Kindly experienced people suggest the pros and cons of the same in this issue

[pipo]

I do not have personnaly any experience on changing the OS block size, but I've been working for long on Ux boxes, and always had good performances, if the Oracle block size is chosen correctly of course ...

[hrishy]

hi

i n case ur databse is OLTP then it is better to have a block size like 4K to 8K i will prefer 8K atleast and dont forget to make ur db_block_size=multiple of os block size as that would ensure you that in a single i/o oracle can fetch atleast 8k of data.improving your i/o

regards
hrishy

[nac]

Hi

Thanx,

I relatedly want to know the impact of changing the default of block size. What are its pros and cons.


It would be much helpful for me and that's the one which I really need

[Halo]

IMO, what matters more is the Oracle block size, not the OS block size.