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Subject: Re: Questions about dump/restore to/from DVD media
In-Reply-To: <20121105051447.6eef32ef.freebsd@edvax.de>
Date: Mon, 05 Nov 2012 03:49:48 -0800
Message-ID: <25974.1352116188@tristatelogic.com>
From: "Ronald F. Guilmette" <rfg@tristatelogic.com>
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In message <20121105051447.6eef32ef.freebsd@edvax.de>, 
Polytropon <freebsd@edvax.de> wrote:

>> >The problem is that delegating compression to a "sub-task" would
>> >imply that dump cannot precisely adjust its output to match the
>> >media size (as the limit is now defined by how good the compression
>> >works).
>> 
>> Correct.  We have both just said the exact same thing in different ways.
>> 
>> In order to have _compression_ of the dump data _and_ still be able to
>> divide the (post-compression) data into nice proper 2KB chunks (as required
>> for DVD+/-R writing) the compression step itself would need to be integrated
>> into the dump program itself (and then, for symmetry, if for no other
>> reason, into restore as well).
>
>Chunk size _and_ media size matter (as dump would have to "know"
>when the media is expected to be "nearly-full" _with_ compression)

Correct.

We are both still just violently agreeing.


Regards,
rfg