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Re: [debian-knoppix] remastering: problems with create_compressed_fs



This is the Knoppix script I use to create the iso:

#!/bin/bash
rm /KNOPPIX/New-Master/KNOPPIX/KNOPPIX
mkisofs -R   /KNOPPIX/New-Source  |  create_compressed_fs -   65536  >
/KNOPPIX/New-Master/KNOPPIX/KNOPPIX
mkisofs -r -J -b KNOPPIX/boot.img -c KNOPPIX/boot.cat   -o
/mnt/windows/new.iso  /KNOPPIX/New-Master
echo "Done"

The only time I have had problems with iso images being too large was when I
forgot to delete stuff I had copied over. I have done a bunch of custom
builds where the only thing I did was create 3 text files in /etc/init.d/,
and the re-compressed iso fit onto a 700meg CD.      PEBKAC.


-Isabella


----- Original Message ----- 
From: "Simon Friedberger" <knoppix@friedberger.de>
To: <debian-knoppix@linuxtag.org>
Sent: Monday, June 30, 2003 5:07 PM
Subject: Re: [debian-knoppix] remastering: problems with
create_compressed_fs


>
>
> Actually i did exactly the same but with mounting with cloop and guess
what? my file had 733....bytes ...? ok so we agree there is some overhead?
but how can i get rid of it? ;)
> smaller block size?
>
> good night
> Simon
>
>
> -- 
> On Mon, 30 Jun 2003 15:38:39 -0700
> Jared Rhine <jared@wordzoo.com> wrote:
>
> > [Klaus == knopper@linuxtag.org on Sun, 29 Jun 2003 23:09:03 +0200]
> >
> > >> i decompressed the KNOPPIX cloop fs and compressed it again ...and
> > >> it had grown about 10mb
> >
> > Klaus> Watch out for hardlinks! This could be the reason.
> >
> > It could also be that compression is not perfectly symmetric; that
> > uncompressing and recompressing again produces a slightly larger file.
> > There's some evidence for this, shown below.  Doing an uncompress
> > followed immediately by a compress expands the KNOPPIX file from
> > 725,032,363 bytes to 727,812,929 bytes.  This probably doesn't happen
> > when mounting using cloop loopback.
> >
> > -- begin --
> >
> > -> cd /mnt/d4/test
> >
> > -> ls -l
> > total 716836
> > -rw-r--r--    1 jared    jared    733317120 Jun 30 03:48
knoppix_v3.2-2003-06-06-en.iso
> >
> > -> sudo mount -t iso9660 -o loop knoppix_v3.2-2003-06-06-en.iso
/mnt/test
> >
> > -> ls -l /mnt/test/KNOPPIX/KNOPPIX
> > -r--r--r--    1 root     root     725032363 Jun  6 09:06
/mnt/test/KNOPPIX/KNOPPIX
> >
> > -> extract_compressed_fs /mnt/test/KNOPPIX/KNOPPIX >
/mnt/d4/test/extracted
> > 29239 blocks of size 65536. Preamble:
> > #!/bin/sh
> > insmod cloop.o file=$0 && mount -r -t iso9660 /dev/cloop $1
> > exit $?
> >
> > Block 0 length 11945 => 65536
> > Block 1 length 30324 => 65536
> > Block 2 length 30546 => 65536
> > Block 3 length 29327 => 65536
> > Block head:78DAECBD877F1CD5
> > Block tail:61CF0E315D18D948
> > Block 4 length 34020 => 65536
> > Block 5 length 18788 => 65536
> > Block 6 length 9368 => 65536
> > [...]
> >
> > -> ls -l .
> > total 2589964
> > -rw-r--r--    1 jared    jared    1916207104 Jun 30 04:13 extracted
> > -rw-r--r--    1 jared    jared    733317120 Jun 30 03:48
knoppix_v3.2-2003-06-06-en.iso
> >
> > -> cat extracted | create_compressed_fs - 65536 > recompressed
> > Block#     0 size  65536 ->  11963 [compression ratio  18%, overall:
18%]
> > Block#     1 size  65536 ->  30321 [compression ratio  46%, overall:
32%]
> > Block#     2 size  65536 ->  30545 [compression ratio  46%, overall:
37%]
> > [...]
> >
> > -> ls -l /mnt/test/KNOPPIX/KNOPPIX /mnt/d4/test
> > -r--r--r--    1 root     root     725032363 Jun  6 09:06
/mnt/test/KNOPPIX/KNOPPIX
> >
> > /mnt/d4/test:
> > total 3301420
> > -rw-r--r--    1 jared    jared    1916207104 Jun 30 04:13 extracted
> > -rw-r--r--    1 jared    jared    733317120 Jun 30 03:48
knoppix_v3.2-2003-06-06-en.iso
> > -rw-r--r--    1 jared    jared    727812929 Jun 30 05:29 recompressed
> >
> > -- end --
> >
> > -- jared@wordzoo.com
> >
> > "A black hole is where God is dividing by zero."
> >         -- attributed to Roger Smith
> > _______________________________________________
> > debian-knoppix mailing list
> > debian-knoppix@linuxtag.org
> > http://mailman.linuxtag.org/mailman/listinfo/debian-knoppix
>
>
> -- 
> _______________________________________________
> debian-knoppix mailing list
> debian-knoppix@linuxtag.org
> http://mailman.linuxtag.org/mailman/listinfo/debian-knoppix

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