Re: Estimation of Backup size

From: Howard J. Rogers <hjr_at_dizwell.com>
Date: Wed, 11 Aug 2004 21:33:07 +1000
Message-ID: <opsckfphzo3d8uqx@shostakovich.dizwell.com>

On 11 Aug 2004 03:31:20 -0700, Ashwin <ashwinkumar_at_engineer.com> wrote:

> Hi,
> Is there any means to estimate the size of RMAN backups and also the
> time.
> Thanks
> Ashwin

How long's a piece of string?

Size depends on whether you're doing incrementals or not. It will be somewhere between zero bytes and the total size of all your control files and data files and archive logs. If you're not doing incrementals, it will be the total size of all your control files, data files and archive logs. Unless you are issuing 'backup tablespace' commands rather than 'backup database' ones.

As for time, what's the medium you're backing up to? What's it's I/O rate? How many channels are you allocating? Is it an alternate Thursday with a full moon?

Rough rule of thumb: the more money you spend, the faster it gets.

Regards
HJR Received on Wed Aug 11 2004 - 06:33:07 CDT