Re: In response to kernel compression e-mail a few months ago.

[Justin Piszcz <jpiszcz@lucidpixels.com>]

On Sun, 14 Oct 2007, Jan Engelhardt wrote:

>
> On Oct 14 2007 15:53, Justin Piszcz wrote:
>>>
>>> What's with all these odd formats, and where is .zip? :)
>>> Somehow... have you tried lrzip?
>> $ apt-cache search lrzip
>> $
>>
>> I tried most of the main ones in the standard testing distribution within
>> Debian.
>
> Debian is not a solution to everything.
>
> http://ck.kolivas.org/apps/lrzip/
>

$ lrzip -L 9 linux-2.6.16.17.tar
Failed to open streams in rzip_fd
Fatal error - exiting

$ lrzip linux-2.6.16.17.tar -o linux-2.6.16.17.tar.lrz
Failed to open streams in rzip_fd
Fatal error - exiting

$ lrzip -l -L 9 linux-2.6.16.17.tar
Bus error

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
22176 abc       20   0 2197m 156m  75m R   93  4.8   0:09.17 lrzip

It must grow to 3.0GB and die (this is on an x86 host)..

$ lrzip -w 1 -l -L 9 linux-2.6.16.17.tar
linux-2.6.16.17.tar - compression ratio 3.127

$ du -sh *lrz
72M     linux-2.6.16.17.tar.lrz

$ lrzip -w 10 -l -L 9 linux-2.6.16.17.tar
linux-2.6.16.17.tar - compression ratio 3.380
$ du -sh *lrz
67M     linux-2.6.16.17.tar.lrz

Does not seem to come close unless I am doing something wrong.

Also, 7z can compress/decompress on stdin and it is multi-threaded (uses 
1.8-2.2 CPU/cores).

>> note that lrzip cannot operate on stdin/stdout

Justin.