RE: share a new 11gR2 feature

  • From: "Matthew Zito" <mzito@xxxxxxxxxxx>
  • To: <dbvision@xxxxxxxxxxxx>
  • Date: Sat, 5 Sep 2009 13:24:18 -0400


I think we're conflating the two different points.  I was commenting only on 
the ability to tell ASM to put certain objects closer to the outside of the 

In almost all of today's arrays, there is a non-relational association between 
the physical disk and the logical devices that are presented to the end host.  
In addition, having large amounts of cache and write re-ordering mitigates the 
performance benefits of placing data on the outside of the disk.

I was just making the point that this is largely inapplicable to people who 
have traditional arrays, and seems to be a feature designed to help encourage 
people that they don't need traditional storage arrays.

I agree that removing the requirement to allocate data for empty objects is a 
good thing.


Matthew Zito
Chief Scientist
GridApp Systems
P: 646-452-4090

-----Original Message-----
From: oracle-l-bounce@xxxxxxxxxxxxx on behalf of Nuno Souto
Sent: Fri 9/4/2009 8:59 PM
Cc: oracle-l@xxxxxxxxxxxxx
Subject: Re: share a new 11gR2 feature
Matthew Zito wrote,on my timestamp of 5/09/2009 2:05 AM:
> This would, indeed, be a useful feature if anyone these days actually 
> ran their data on physical disks. 

Er..... Are you sure you mean that?  What should they use then?  Tapes?

> With today's world of wide-striping, 
> massive array caches, write re-ordering, and storage virtualization, I 
> doubt it will make much difference.

Sorry Mathew, but you got to be joking. What's that got to do with gigabytes of 
allocated space that never is used?  And what exactly is an "array cache" and 
what has that got to do with persistent, unused storage?
"Virtualized" storage?  In what way does that change the fact that storage 
space, in whatever format it may take - virtual or not - is being used for 
absolutely nothing?  Last time I looked virtual is not a synonym for free: it 
still has to be paid for.  Use it to store nothing and you are essentially 
wasting money.  I can show you numerous examples, in fact just about any 
corporation, where such activity would be frowned upon.

> It IS very interesting, though, for the argument that Oracle is gonna 
> continue arguing that you can just buy lots of JBOD arrays and do data 
> resiliency in software, rather than investing in enterprise storage.

I don't think so.  Data resiliency is for data, hence the name.  This is for 
absence of data, a totally different proposition.

Nuno Souto
in sunny Sydney, Australia


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