How about some details here Alexandre...

Like ADSM Server Platform and Version. What type of hardware? Are you
backing up straight to tape? or are you migrating from a disk buffer?

I did have a DLT throughput issue once with ADSM V3 on Windows NT and found
the culprit to be a bad SCSI driver. I updated the SCSI drivers.

Nathan





        -----Original Message-----
        From:   Alexandre Bicas Caldeira [SMTP:abicas AT SERVICE.COM DOT BR]
        Sent:   Monday, September 06, 1999 7:45 AM
        To:     ADSM-L AT VM.MARIST DOT EDU
        Subject:        Performance degradation on DLT tapes

        Hi all,

        I had about 75GB of data to backup on a DLT tape drive. In order to
do
        this i will use 3 tapes with 35GB each.

        During the backup, while filling the first tape, I had an aggregate
data
        transfer rate equal to 1.3MB/s. That was ok to me.  When ADSM asked
me
        to insert an scratch volume on the drive (the second tape), I did
it,
        but I had a loss of performance: 0.4MB/s. On the third tape my
        performance went to 0.3MB/s ! ! ! ! !

        This machine is still backing up and I need to use it, but I'm
afraid
        that the backup performance will degrade even more !

        Does anyone know what can be causing this ?!
        There is nothing using my network, neither my computer; just ADSM.

        Thanks,
        ________________________________________________
        Alexandre Bicas Caldeira - abicas AT service.com DOT br
        Service IT Solutions - http://www.service.com.br
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