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From: tsouth@pro-pac.cts.COM (Todd South)
Newsgroups: comp.sys.apple
Subject: Re: Optimizing (or why the 00's?)
Message-ID: <8806271916.AA10419@crash.cts.com>
Date: 27 Jun 88 15:10:10 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: pnet01!pro-simasd!pro-pac!tsouth@nosc.mil
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In Article <8806270057.aa23609@SMOKE.BRL.ARPA> PGOETZ@LOYVAX.BITNET writes:

> Lazlo: Optimizing does not mean writing 0s to unused portions of the disk.
> That would do nothing for performance.

> Phil Goetz

Phil,

        I know one half of the team very well, and he has stated (I believe
it is also in the documentation) that this is exactly what the optimizer
does in DDD Pro.  In the Huffman algorythm, I think that Hex 00 is supposed
to be the single character that takes the fewest bits to express.  Therefore,
if one writes 00's to all unused area's on the disk the total compression of
the disk would be smaller.  Remember, we are talking about a *disk* packer,
not a file compressor.  It looks only at the raw data on a track.

Todd South

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