On Tue, Mar 07, 2006 at 12:07:25PM -0800, Ram TK Krishnamurthy wrote:
> You generally do not use holding disks when backing up to disks.
> 
> tk
> 
> FM wrote:
> >Hello,
> >
> >Do I need a holdingdisk when I using hard drive backup ?
> >
> >I have a lots of iowait because of the copy from holding disk to virtual
> >tape even if the holding disk is on internal SCSI drives and tapes are
> >on an extrenal SCSI array (using sata drives)


Why not Ram?  Without a holding disk only one client DLE can
be dumped at a time.  The holding disk is to allow multiple
DLEs to collect simultaneously, only transfered to "tape"
when complete.  Without a holding disk the DLE must be
dumped "directly to tape" eliminating all parallelism.

-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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