On Thursday 08 July 2004 08:50, Joshua Baker-LePain wrote:
>On Thu, 8 Jul 2004 at 8:35am, Gene Heskett wrote
>
>> On Thursday 08 July 2004 01:32, Alexey I. Froloff wrote:
>> >* Alexey I. Froloff <raorn@> [040707 14:10]:
>> >> P.S. Right now I figured how to turn HW compression off (with
>> >> mt utility) and started amtapetype again...
>> >
>> >Thanks to all for your help. amtapetype finished successfully.
>> >
>> >$ /usr/sbin/amtapetype -e 100g -f /dev/nst0 -t "HP-C7971A"
>> >Writing 1024 Mbyte compresseable data: 25 sec
>> >Writing 1024 Mbyte uncompresseable data: 72 sec
>> >WARNING: Tape drive has hardware compression enabled
>>
>> Please disable this as it hides the true tapesize from amtapetype
>> AND amanda. amanda can do a much better job of filling up a tape
>> if amanda knows how much a tape can hold. You can use the
>> optional gzip compressor on portions of the system to much better
>> advantage in terms of achieved compression ratios, and generally
>> can stuff more data onto a tape than using the hardware compressor
>> can do. Here, under what would be termed ideal conditions, I've
>> had amanda email me and rep[ort that it just put a bit over 12Gb
>> on a 4Gb tape that has the last 370megs reserved for something
>> else I'm doing here.
>
>Actually Gene, for this drive disabling hardware compression isn't
>necessary. It's an LTO/Ultrium drive, and those are actually smart
> enough to not compress already compressed data. Notice (below) how
> he still gets the full 100GB native capacity? With those drives,
> you get the best of both worlds -- you can mix software and
> hardware compression. Very, very slick.
And a bit expen$ive for my retired blood. I've spent $200+ on a fresh
pair of drives here since the first of the year, and they are both
dead now, acting like worn out heads. So if I ever get this machine
stable enough to worry about amanda, I'll see if I can make amanda
use dvd+-rw's instead. But right now the video card died yesterday,
and an atempt to recomipile kde-3.2.3 is meeting with a bus error in
the middle of the qt-x11-free-3.2.3 build. Hello... Bus error?
Nothing in the logs, nada, zip zero.
>> >Estimated time to write 2 * 102400 Mbyte: 14400 sec = 4 h 0 min
>> >wrote 3244032 32Kb blocks in 99 files in 7310 seconds (short
>> > write) wrote 3244032 32Kb blocks in 198 files in 7666 seconds
>> > (short write) define tapetype HP-C7971A {
>> > comment "just produced by tapetype prog (hardware compression
>> > on)" length 101376 mbytes
>> > filemark 0 kbytes
>> > speed 13871 kps
>> >}
--
Cheers, Gene
There are 4 boxes to be used in defense of liberty.
Soap, ballot, jury, and ammo.
Please use in that order, starting now. -Ed Howdershelt, Author
Additions to this message made by Gene Heskett are Copyright 2004,
Maurice E. Heskett, all rights reserved.
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