On Mon, Aug 13, 2007 at 12:48:06PM +0100, Rory Beaton wrote:
> Quoting Jon LaBadie <jon AT jgcomp DOT com>:
> 
> > On Sat, Aug 11, 2007 at 02:28:10PM +0100, Rory Beaton wrote:
> > >
> > > grunt:/usr/sbin # amtapetype  -o -e 80g -f /dev/nst0
> > > Writing 512 Mbyte   compresseable data:  94 sec
> > > Writing 512 Mbyte uncompresseable data:  82 sec
> > > Estimated time to write 2 * 81920 Mbyte: 26240 sec = 7 h 17 min
> > > wrote 2490330 32Kb blocks in 95 files in 12562 seconds (short write)
> > > wrote 2477223 32Kb blocks in 189 files in 12784 seconds (short write)
> > > define tapetype unknown-tapetype {
> > >     comment "just produced by tapetype prog (hardware compression off)"
> > >     length 78236 mbytes
> > >     filemark 4461 kbytes
> > >     speed 6272 kps
> > > }
> > >
> >
> > DAT tapetype reports have varied as to whether there was any
> > filemark at all.  I don't know why.  My own testing on two
> > HP DATs (dds2 & dds3) showed no filemarks.
> >
> > You might do another tapetype run to check if it is consistant.
> 
> 
> grunt:/usr/sbin # amtapetype -o -f /dev/nst0
> Writing 512 Mbyte   compresseable data:  83 sec
> Writing 512 Mbyte uncompresseable data:  83 sec
> Estimated time to write 2 * 1024 Mbyte: 332 sec = 0 h 5 min
> wrote 2437131 32Kb blocks in 7453 files in 28358 seconds (short write)
> wrote 2096995 32Kb blocks in 12865 files in 40050 seconds (short write)
> define tapetype unknown-tapetype {
>     comment "just produced by tapetype prog (hardware compression off)"
>     length 90796 mbytes
>     filemark 2011 kbytes
>     speed 2212 kps
> }

You skipped the -e option so amtapetype defaulted to a very
small estimated capacity and wrote lots of small files.
It probably was not streaming very well.

jl
-- 
Jon H. LaBadie                  jon AT jgcomp DOT com
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