On one of our databases we have compression ratio close to 3, I think
that Oracle uses algorithm that is similar to gzip. One note to
remember is that RMAN does not copy empty untouched blocks, so if you
have large preallocated tablespaces you will see that your backups are
much less than real database size even without compression.
On Tue, 21 Dec 2004 10:08:41 -0000, Howard Latham
<howard.latham_at_rsmb.co.uk> wrote:
>
> Anyone have real experience of the compression ratio with rman on 10g to
> disk ?
> My 300 gig database seems to be backed up into 40gig - Yes I know
> I could validate it but it gobbles CPU and took 11 hours to do the
> backup so I
> just want a reality check!
>
> The manual says 2 to 4 times.
>
> And Yes I also know I have to test recovery sometime but that will be
> out of
> Hours !
>
> Oh and Happy Christmas to you all
>
> Howatd Latham
>
> --
> http://www.freelists.org/webpage/oracle-l
>
--
Edgar
--
http://www.freelists.org/webpage/oracle-l
Received on Tue Dec 21 2004 - 10:26:43 CST
