(1) Is it possible you have hardware compression activated, and that
your compression algorithms are bickering and end up taking up more
space on the tape? Just a thought. Otherwise, your 33.9G ought to fit on
two 20G tapes. (2) Another possibility would be that you have an issue
with tape errors and perhaps need to run a cleaning tape or get new
tapes? That could cause gaps and such that end up not utilizing the full
capacity of the tapes. (3) I don't know if it applies to the type of
tape you are using, but speed issues caused by other aspects of your
hardware or backup configuration could cause the tape to be starting and
stopping, which could eat up space.


---------------

Chris Hoogendyk

-
O__ ---- Systems Administrator
c/ /'_ --- Biology & Geology Departments
(*) \(*) -- 140 Morrill Science Center
~~~~~~~~~~ - University of Massachusetts, Amherst



---------------

Erdös 4




Wayne Thorpe wrote:
> Tried setting 'runtape 1' already, tape did not get past 42.7%
>
> This is what happed ....
> ______________
> /These dumps were to tape tapebac05.
> *** A TAPE ERROR OCCURRED: [No more writable valid tape found].
> Some dumps may have been left in the holding disk.
> Run amflush to flush them to tape.
> The next tape Amanda expects to use is: a new tape.
> The next new tape already labelled is: tapebac06./
> /.../
> /.../
> /.../
> /USAGE BY TAPE:
> Label Time Size % Nb Nc
> tapebac05 3:23 17479168K 42.7 7 0
> /
> /_____________________________
> /
>
> */"Martin.Hepworth" /* wrote:
>
>
> Wayne
> So what happens if you change runtapes to 1? Ie use a minimum of 1
> tape.
>
> --
> Martin Hepworth
> Snr Systems Administrator
> Solid State Logic
> Tel: +44 (0)1865 842300
>
> > -----Original Message-----
> > From: owner-amanda-users AT amanda DOT org
> [mailto:owner-amanda-users AT amanda DOT org]
> > On Behalf Of Wayne Thorpe
> > Sent: 21 November 2007 13:18
> > To: amanda-users AT amanda DOT org
> > Subject: Wasted Space, capacity under 50% over multiple tapes
> >
> > Questions: How can I get all 33.9 GB of data on my 40GB tape
> media? How
> > can I get as much data as possible on first tape before moving
> to second
> > tape?
> >
> >
> > Hello,
> > Summary or problem is as follows,
> > -OS: Solaris 9
> > -Version #: AMANDA 2.5.1p2
> > -TapeInfo: Quantum DLT4000, 40GB Native, 80GB,
> > -Driver Info: /dev/rmt/0n (no hardware compression)
> > -Problem: I have 33.9 GB of comressed data spread accoss 14
> different
> > partitions that are scheduled for backup to tape at level 0
> weekly. After
> > software compression, each partition dump size range between
> 2.3MB and
> > 7.8GB.
> > The problem is that I getting a lot of wasted space on the tape
> writes.
> > Runtapes in amanda.conf = 2. The first fills up to only 33.4%
> and then
> > AMANDA moves job to a second tape filling up to 45.6%.
> > In previous backups a 'ran out of tape' error appeared after
> using both
> > tapes at under 50% and I would be forced to do a amflushed the next
> > morning to a 3rd tape.
> >
> >
> > Detail of Settings in amanda.conf:
> > inparallel 4
> > dumporder "sSsS"
> > taperalgo firstfit
> >
> > runtapes 2
> > tpchanger "chg-zd-mtx"
> > tapedev "/dev/rmt/0n"
> > tapetype QUANTUM-DLT4000
> >
> > define tapetype QUANTUM-DLT4000 {
> > comment "Quantum DLT4000 (hardware compression disabled)"
> > length 39936 mbytes
> > filemark 4 kbytes
> > speed 1008 kps
> > }
> > define dumptype comp-root-tar {
> > root-tar
> > comment "Root partitions with compression"
> > compress client fast
> > tape_splitsize 3994 mbytes
> >
> >
> > Output from Mail Report:
> > These dumps were to tapes tapebac07, tapebac08.
> > The next 2 tapes Amanda expects to use are: 2 new tapes.
> > The next 2 new tapes already labelled are: tapebac09, tapebac10.
> >
> >
> > STATISTICS:
> > Total Full Incr.
> > -------- -------- --------
> > Estimate Time (hrs:min) 0:09
> > Run Time (hrs:min) 8:38
> > Dump Time (hrs:min) 6:16 6:16 0:00
> > Output Size (meg) 33944.8 33944.8 0.0
> > Original Size (meg) 84163.4 84163.4 0.0
> > Avg Compressed Size (%) 40.3 40.3 --
> > Filesystems Dumped 14 14 0
> > Avg Dump Rate (k/s) 1539.6 1539.6 --
> >
> > Tape Time (hrs:min) 6:44 6:44 0:00
> > Tape Size (meg) 33945.6 33945.6 0.0
> > Tape Used (%) 85.0 85.0 0.0
> > Filesystems Taped 14 14 0
> >
> > Chunks Taped 19 19 0
> > Avg Tp Write Rate (k/s) 1434.7 1434.7 --
> >
> > USAGE BY TAPE:
> > Label Time Size % Nb Nc
> > tapebac07 3:07 15724M 39.4 11 13
> > tapebac08 3:37 18222M 45.6 3 6
> >
>
>