Re: Oracle Tnuning---Block Size, How much difference?

In article <q3KS2.884$jz6.3138781_at_firenze.visi.net>,   "Sean Zhang" <sean_at_cnfei.com> wrote:
> Hello, Everybody,
>
> Recently I upgraded our system from Oracle 8 ->Oracle 8i,
> ( in Sun E3000 with Solaris 2.6).
> During the upgrade, I used Export utilities to build a whole new
> database, and the block size was also changed from 4K-> 2K.
> Now I feel the new system is a bit slower than the old system. I read
> some technical books , which say bigger block size could dramatically
> increase the performace, but Oracle documentations stress the
> default block size (2 K) is optimal for our system. I don't know which is
> true
> OR whether the change of block size is the problem making the new
> system slower.
>
> Any suggestions and advices are greatly appreciated.
>
>

I have twice been associated with database migrations/upgrades where the block size was changed; once from 2K to 4K under VMS and from 4K to 8K under Unix. Both times there were noticable performance improvements accross the board. We had re-organized the VMS db just a couple of weeks prior to be able to eliminate the re-org effect of the upgrade from the comparision so I truely believe 4k is the smallest exceptable Oracle block size.

The Oracle 7 manual said bigger was better. I think that the only reason that 8's says 2k is OK is because 2k is the default on most platforms and Oracle does not want to defend leaving the default at a less than optimal setting. -- Mark D. Powell -- The only advice that counts is the advice that  you follow so follow your own advice --

-----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own Received on Mon Apr 19 1999 - 15:01:28 CDT