LTO drives will "crawl" unless they are streamed.

The LTO blocksize should be set as high as possible, 256KB is not to
large.

If your disk and application cannot write at 15 MB/sec, the best you can
expect is a few MB/sec.  There is no in-between.

Orville L. Lantto
Datatrend Technologies, Inc.  (http://www.datatrend.com)
IBM Premier Business Partner
121 Cheshire Lane, Suite 700
Minnetonka, MN 55305
Email: Orville.Lantto AT datatrend DOT com





Lars Bebensee <LBebensee AT HAITEC DOT DE>
Sent by: "ADSM: Dist Stor Manager" <ADSM-L AT VM.MARIST DOT EDU>
08/13/02 09:24 AM
Please respond to "ADSM: Dist Stor Manager"


        To:     ADSM-L AT VM.MARIST DOT EDU
        cc:
        Subject:        Tape Performance on 3580


Hi guys,

this is actually not a TSM question but one for the hardware gurus. We are
running a backup under AIX using the savevg command and Ultrium 3580 tape
drives. With topas I can see a data transfer rate of about 1MB/sec. We
attached the drives via Fibre Channel and a SAN Data Gateway. The
blocksize
of the drive was set to 2048 (since one of the SAN guys told me FC
transfers with a blocksize of 2048). I started savevg with "-b4" meaning
to
write 4x512Byte blocks (=2048). With the mentioned speed the drives are
seriously crawling. Am I missing out something here? Any clues??

Thanks

Lars