Date: Wed, 27 Aug 2008 12:40:32 -0700 (PDT)
On Aug 27, 2:24 pm, sybra..._at_hccnet.nl wrote:
> On Wed, 27 Aug 2008 12:01:19 -0700 (PDT), artme..._at_yahoo.com wrote:
> >Sorry for the double post, but as we are reading and seeing BACKUPSET
> >and BACKUPPIECE........we can see that a piece is part of a set. But,
> >if you need to break up the set into pieces, why not just make smaller
> >size sets??
> A datafile can not span multiple backupsets.
> A datafile can span multiple backuppieces.
> You could configure 2G backuppieces (max filesize for 32-bit files on
> some Unixes) and have a backupset of unlimited size.
> >Also, how does this relate to FILESPERSET?
> All files in a set will be
> a) simultaneously opened
> b) simultaneously backupped
> c) get multiplexed in one backupset, so 1 block for datafile 1 is
> followed by one block for datafile 2 etc.
> If you have all your datafiles on few disks, NOT configuring
> filesperset (Oracle by default tries to back up as much as possible)
> create an I/O bottleneck.
> You could argue filesperset always needs to be 1.
> >We're all new to this.....
> >Thank you
> Sybrand Bakker
> Senior Oracle DBA
Thank you Sybrand,
I'm sure this has a lot to do with performance. So, we'll take this and try to play and see some stats. Received on Wed Aug 27 2008 - 14:40:32 CDT