Re: DB_BLOCK_SIZE

From: Doug Smith <dsmith_at_gulfaero.com>
Date: 1996/12/03
Message-ID: <dsmith.183.0009502C_at_gulfaero.com>#1/1


In article <01bbdef1$008b3bb0$0f0200c0_at_anovick> "Andrew Novick" <anovick_at_world.std.com> writes:
>From: "Andrew Novick" <anovick_at_world.std.com>
>Subject: Re: DB_BLOCK_SIZE
>Date: Tue, 3 Dec 1996 05:35:23 GMT
 

>Unless you're very low on memory (paging, etc) I always suggest using the
>biggest block size allowed. On NT 3.51 it's 8K.

>Dana Stockler <stockler_at_ingdata.no> wrote in article
><329C9ED7.7420_at_ingdata.no>...
>> Kevin Loney wrote:
>> >
>> > Michael Bethke wrote:
>> > >
>> > > What is the max. DB_BLOCK_SIZE (ORACLE 7.3.2.2) on Solaris 2.4?
>> > > What is the highest value you've ever heard from?
>> > >
>> >
>> > Max I've seen used: 32K
>>
>> Anybody have any opinions as to the best (I know, too simplistic!)
>> database block size to use on Windows NT 3.51?
>>
>> Regards,
>>
>> -----------------------------------------------------------
>> Dana Stockler
>> -----------------------------------------------------------
>> Home: Solstadlia 10, 1364 Hvalstad, Norway ((+47)66789741)
>> Work: IngeniørData as, Strøket 9, 1370 Asker, Norway
>> Email: stockler_at_ingdata.no
>> -----------------------------------------------------------
>>

It's a tuning issue. You have to understand the application and machine setup to make an informed decision.

If an application does alot of sweeping sql selects ( such as an end user reporting database) it might make sense to have a larger block size. This way you might be able to eliminate some physical reads to the disk drive because the next block it is looking for will already be in memory.

If an application is an online olap application then it might make sense to have a smaller block size. This way you aren't filling and flusing the buffers with useless data. It takes longer to read a larger block size.

Buffer sizes (memory) is the other consideration. The more the better. Received on Tue Dec 03 1996 - 00:00:00 CET

Original text of this message