Dustin J. Mitchell wrote:
On Fri, Aug 27, 2010 at 2:41 PM, Chris Hoogendyk
<[email protected]> wrote:
There was an exchange on the list in the last few months where I asked that
question and Dustin replied. He said that the historical algorithm had a
strong preference for an already written tape if one was available that
could be written to. I think he said that now that the new taper was out he
was thinking about implementing a more sane algorithm.
Wow, I'm cited twice as historical precedent!
If you look closely at amanda-taperscan(7), you'll see that the
unknown component of the algorithm that has changed in more recent
versions is whether the changer is fast-searchable. In the past, only
chg-zd-mtx+barcodes was searchable. Even chg-disk acted like a
barcode-less changer, and just scanned slots in order to find a tape.
That's an interesting nuance. chg-zd-mtx+barcodes is exactly what I have
on all my installations. That explains why others might have had
different experiences.
The traditional algorithm will "stumble across" new tapes with a
non-fast-searchable changer, but with a fast-searchable changer, it
will always search for the oldest reusable tape, paying no attention
to new tapes.
It's unfortunate, but it's the way things have worked historically.
--
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Chris Hoogendyk
-
O__ ---- Systems Administrator
c/ /'_ --- Biology & Geology Departments
(*) \(*) -- 140 Morrill Science Center
~~~~~~~~~~ - University of Massachusetts, Amherst
<[email protected]>
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Erdös 4
