Re: block chg tracking
From: Mladen Gogala <mgogala_at_yahoo.com>
Date: Sun, 15 Feb 2015 12:24:14 -0500
Message-ID: <54E0D63E.7090703_at_yahoo.com>
On 02/15/2015 11:47 AM, Jared Still wrote:
> Hi Mladen,
>
> Though dedup reduces the size on the backend, it does nothing for
> database impact.
>
> As you know BCT reduces the reads on the db by RMAN, so I am a little
> confused by this statement.
Date: Sun, 15 Feb 2015 12:24:14 -0500
Message-ID: <54E0D63E.7090703_at_yahoo.com>
On 02/15/2015 11:47 AM, Jared Still wrote:
> Hi Mladen,
>
> Though dedup reduces the size on the backend, it does nothing for
> database impact.
>
> As you know BCT reduces the reads on the db by RMAN, so I am a little
> confused by this statement.
That is true, but the goal is not reducing the reads, the goal is to restore database in the shortest time possible. De-duplication also speeds things up, because everything is read, but not everything is written. You get far fewer disk writes and, if the storage medium is connected by network, far less network traffic. Given that a full backup must be restored, the difference is whether there will be a need for applying additional incremental backups.
-- Mladen Gogala Oracle DBA http://mgogala.freehostia.com -- http://www.freelists.org/webpage/oracle-lReceived on Sun Feb 15 2015 - 18:24:14 CET