Re: block size

From: <>
Date: Mon, 26 Oct 2009 15:42:42 -0400
Message-Id: <>

I'm not a DW guy at all. We have one at our company, but, since DW are mostly read databases, isn't that what the big block size would be good for. Grab a ton of info and through it into cache/memory? OLTP, smaller block, less writing for insert, updates and deletes. That's the only thing that comes to mind for me. Lyall

-----Original Message-----
From: Niall Litchfield <> To: ORACLE-L <> Sent: Mon, Oct 26, 2009 2:32 pm
Subject: block size

so, discussion with DW architect today  

"but this isn't OLTP,this is DW, in a datawarehouse you want the biggest block size you can have".

my question to you (and him)  

"why? What's the theory and evidence for this?"

In other words *why* do people think this? Note I'm specifically not after pointers to religious wars (entertaining though these are) but to particular logical arguments. This chap is bright (and like me somewhat loquacious) and I disagree with him, the resultant discussion could go on a while so I'm hoping to short circuit it.

Platform is RHEL 4 64bit, 64bit Oracle 11gR1. This is *not* a warehouse with huge amounts of data (say, 500mb per year).

Niall Litchfield
Oracle DBA

Received on Mon Oct 26 2009 - 14:42:42 CDT

Original text of this message