Re: Raw Partitions and Oracle

Billy Verreynne <vslabs_at_onwe.co.za> wrote in article <6e2leh$lca$1_at_hermes.is.co.za>...
> John Bishop wrote in message

 <35048AAE.B28DEABA_at_atl.mediaone.net>...
> >I'm curious to see how many folks are actually running raw vs.
 file. In
 the
> >DBA class I went to I was given a doc stating that running raw is
 more of a
> >hassle for backups (i.e. using dd instead of tar, cp...) and the
 the raw
 idea
> >(unless you are using a third party backup tool because of
 limitations with
> >dd) really is not worth it.

In answer to John Bishop:

	Most of the large sites I have worked at recently are on raw.
	There is very little 'extra hassle' it's just a state of mind.  viz:
	Do you have Oracle DBA's who have to handle the Unix systems, or
	do you have Unix system administrators who happen to handle 
	allocating raw logical volumes for DBA's.

> The only problem I have with raw devices is that there are space
 overheads.
> On a 1GB raw device I can get Oracle to only use the first 980MB.
 And if you
> run a large database then you have a couple of GBs of raw space
 that you can
> not use.

Billy, this sounds odd. What is the problem ?

I know that the logical volume/raw devices has to be one Oracle block larger
than the 'datafile' that Oracle is aware of, but 20MB seems a bit large. Is
this an extent-related thing you use to cover gc_lock granularity ?

Jonathan Lewis. Received on Tue Mar 10 1998 - 00:00:00 CST