Unofficial cheatcode for those who miss the old official home= cheatcode

[Werner P. Schulz]

.. I can't believe this result. What did you compress, Knoppix CD or DVD? How long (exact) will it take to compress with sqashfs and with cloop (create_compressed_fs)?

... now I have done a test for my own.

using virtual machine (VirtualBox), 1 GB RAM, swap partition 1 GB

using Knoppix CD-Version 6.4.4

decompress /KNOPPIX/KNOPPIX (705211 K => 100%) to directory '/remaster' (2054135 K)

losetup /dev/cloop0 /media/sr0/KNOPPIX/KNOPPIX
mount -t iso9660 /dev/cloop0 /knoppix/loop
rsync -aH /knoppix/loop/* /remaster

a) compress '/remaster' to KNOPPIX

genisoimage -R -U -no-bak -quiet \
    /remaster | create_compressed_fs -q -B 65536 \
    -f /tmp/knoppix_tmp - /knoppix/KNOPPIX/KNOPPIX

size of new KNOPPIX: 740461 K (104,96%)

compression time: 7 min 03 sec


b) compress '/remaster' to KNOPPIX.squasfs

mksquashfs-lzma /remaster 
   \/knoppix/KNOPPIX/KNOPPIX.squashfs

size of KNOPPIX.squashfs: 719876 K (102,08%)

compression time: 6 min 42 sec

I think the differences are not worth the trouble to leave a well established compression method.


Greetings Werner * http://www.wp-schulz.de/knoppix/summary.html
Own Rescue-CD with Knoppix (Knoppix V6.4.4 remaster)

[utu]

@ Werner

Would a comparison of expansion times be comparable?
Thanks.

[kl522]

I think the differences are not worth the trouble to leave a well established compression method.

I don't want to get into the war of the compression speed comparison, as I mentioned earlier, as some of the comparison what not a fair one, basically they did not use the same compression algorithm, it is not apple to apple.

However, I would like to dispute this point about cloop being the well eastablished compression method.

Which is more established compression method ?

Maybe my knowledge is skewed but here is what I know :-

1. Squashfs has long existed if not as long as cloop compression.
2. Squashfs is accepted into stock kernel a few versions back but cloop is still an external patch.
3. You can find squashfs in almost all embedded devices, including your typical home routers, home ADSL modems, home media players, home appliances such as TVs and so on. If you count the number of seats ( linux OS ) uses squashfs compared to cloop, squashfs is many many times more widespread than cloop..
4. Just run this utility on the compression file system :-

      $ file /mnt-system/KNOPPI/KNOPPIX
KNOPPIX: POSIX shell script text executable
     
     $ file /mnt-system/KNOPPIX/KNOPPIX.sq
KNOPPIX.sq: Squashfs filesystem, little endian, version 4.0, 630912472831 bytes, 189043 inodes, blocksize: 147 bytes, created: Mon Jan  7 04:52:16 1991

Now even a utility like 'file' knows about squashfs, which is more established ?

[Werner P. Schulz]

... with

".. to leave a well established compression method"

I did mean, that Klaus Knopper may have good reasons not leaving a well established compression method for his Knoppix distribution.

@ utu

I have no comparison of expansion times. And I only did my compression test because I couldn't believe the result of dinosoep.



Greetings Werner * http://www.wp-schulz.de/knoppix/summary.html
Own Rescue-CD with Knoppix (Knoppix V6.4.4 remaster)

[kl522]

... with I did mean, that Klaus Knopper may have good reasons not leaving a well established compression method for his Knoppix distribution.

He should submit this cloop patches to the kernel team if he continues to want to use it for Knoppix. The knoppix kernel, there are still two modules which are compiled outside the standard distro, ie the aufs2 and cloop. I am seeing there is significant progress in integrating aufs2 into the standard distro, it will not be long aufs2 will be part of a standard kernel source.

cloop will soon be left as the only one needed as an external patch. I am not aware that there is any effort to put that into standard kernel source. I hope I am wrong in this.