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Posted: 10 Nov 2011, 10:08
by lal
EDIT: NOTE: This is *not* about the "best" compression program in general, but about rar achieving higher compression ratios than bzip2 and gzip! Nothing more.
7bit wrote:
lal wrote:gzip and bzip2 compress with the highest compression ratio by default. RAR usually compresses better than both of them, so the archive was most probably not created with a high compression ratio mode. I'm fully with you about FOSS and open data formats, but that one you have to give to the rarlabs I'm afraid.
LOL! :lol: :lol: :lol: :lol: :lol: :lol:
Give me a proof!
No problem. Just one prominent example:
Code: Select all
falken@wopr ~/compressiontest$ time rar a -m5 -md4096 -r -s linux-3.0.8.rar linux-3.0.8/ >/dev/null
real 6m34.607s
user 2m24.089s
sys 0m6.864s
falken@wopr ~/compressiontest$ time tar cjf linux-3.0.8.tar.bz2 linux-3.0.8
real 1m50.908s
user 1m19.237s
sys 0m2.488s
falken@wopr ~/compressiontest$ du -sb *
430840596 linux-3.0.8
72082921 linux-3.0.8.rar
78257952 linux-3.0.8.tar.bz2
falken@wopr ~/compressiontest$ rar | grep ^RAR; bzip2 --version 2>&1 | grep Version
RAR 4.00 beta 3 Copyright (c) 1993-2010 Alexander Roshal 17 Dec 2010
bzip2, a block-sorting file compressor. Version 1.0.5, 10-Dec-2007.
falken@wopr ~/compressiontest$
And for comparison rar at default settings:
Code: Select all
falken@wopr ~/compressiontest$ time rar a -r linux-3.0.8.rar linux-3.0.8/ >/dev/null
real 1m55.262s
user 1m16.513s
sys 0m6.152s
falken@wopr ~/compressiontest$ du -sb linux-3.0.8.rar
113306761 linux-3.0.8.rar
falken@wopr ~/compressiontest$
You can see that rar is trading compression ratio for execution time by default. Set to the highest compression level rar kicks bzip2's ass, I'm afraid. (In terms of file size only!)
Posted: 10 Nov 2011, 10:30
by fossala
Anyway, xz is the best oss option. It is why arch, slackware, fedora, gcc tool kit freebsd and funtoo all use it. bzip2 is good it just doesn't stand up anymore. The only reason why some people still use it is because xz takes alot of cpu cycles.
Posted: 10 Nov 2011, 10:31
by woody
7zip is pretty good.
Posted: 10 Nov 2011, 10:39
by fossala
The good thing about 7zip is that it is easy to use on all operating systems.
Posted: 10 Nov 2011, 10:41
by woody
Examples at default compression level:
Code: Select all
$ time tar cvfz openbox-3.5.0.tar.gz openbox-3.5.0
... (921591 bytes)
real 0m0.246s
user 0m0.247s
sys 0m0.010s
$ time tar cvfj openbox-3.5.0.tar.bz2 openbox-3.5.0
... (727310 bytes)
real 0m1.147s
user 0m1.130s
sys 0m0.030s
$ time 7z a openbox-3.5.0.7z openbox-3.5.0
... (621417 bytes)
real 0m1.639s
user 0m2.793s
sys 0m0.107s
$ time tar cvfJ openbox-3.5.0.tar.xz openbox-3.5.0
... (616332 bytes)
real 0m2.965s
user 0m2.923s
sys 0m0.067s
Posted: 10 Nov 2011, 10:45
by fossala
Everyone is doing it at default compression ratios, why? You shouldn't be bothers with that, what you need to check is either
1, compressed to the same size which is quicker.
2, how small can it compress with the highest compression.
Because packagers or devs don't agree with the same defaults doesn't make one better than the other.
Posted: 10 Nov 2011, 11:19
by sixty
There are some good (though outdated) comparisons here:
http://www.uwe-freese.de/sonstiges/prod ... acker.html
Posted: 10 Nov 2011, 11:55
by 7bit
We did not compare the time the compressions take. The more compression is wanted, the better the input must be analysed, so it takes longer.
My one and only point is:
It does not matter how much the stuff gets squeezed together, it matters how many people are able to get it unsqeezed again.
So zip and tar/gzip are still the winner!
And note this down, all of you:
I will never ever install non-Debian free software on my machine just to unpack a bunch of SVG graphics for key caps I will never ever buy for myself, because it is always best to use the key caps on a keyboard for which they'd been made for!
Phantom FTW!
Posted: 10 Nov 2011, 13:19
by Soarer
7bit wrote:My one and only point is:
It does not matter how much the stuff gets squeezed together, it matters how many people are able to get it unsqeezed again.
You were the one that started comparing compression ratios!!
Anyway, just get 7zip / p7zip and stop telling the other 99.99999997% of people to comply with your demands!
Posted: 10 Nov 2011, 16:31
by 7bit
Soarer wrote:...
Anyway, just get 7zip / p7zip and stop telling the other 99.99999997% of people to comply with your demands!
Write a free unrar which can unrar the latest rar files and I will never ever complain again.
Also, everybody knows that there are only 99.999835292% of all home-computers running Windows!
@sixty: when do you fix your browser, so we don't have to live with that annoying gap between quotes and answers?
Posted: 10 Nov 2011, 16:47
by fossala
There was a new free unrar. It was developed for os x but is being released for windows and *nix as well. I will hunt around for a link later.
Posted: 10 Nov 2011, 17:03
by 7bit
fossala wrote:There was a new free unrar. It was developed for os x but is being released for windows and *nix as well. I will hunt around for a link later.
You will get free Round 5 key caps if you don't find it!
Posted: 10 Nov 2011, 17:15
by sixty
fossala wrote:There was a new free unrar. It was developed for os x but is being released for windows and *nix as well. I will hunt around for a link later.
I used this on OSX back in the day, think it also compiles on Linux by now:
http://wakaba.c3.cx/s/apps/unarchiver
Posted: 10 Nov 2011, 18:59
by Soarer
7bit wrote:Write a free unrar which can unrar the latest rar files and I will never ever complain again.
p7zip doesn't work?
Posted: 10 Nov 2011, 19:13
by 7bit
Soarer wrote:7bit wrote:Write a free unrar which can unrar the latest rar files and I will never ever complain again.
p7zip doesn't work?
:~> 7z e Moogle2SVG.rar
7-Zip 9.04 beta Copyright (c) 1999-2009 Igor Pavlov 2009-05-30
p7zip Version 9.04 (locale=en_US.UTF-8,Utf16=on,HugeFiles=on,4 CPUs)
Processing archive: Moogle2SVG.rar
Extracting Alt.svg Unsupported Method
Extracting CapsLock.svg Unsupported Method
Extracting Control.svg Unsupported Method
Extracting Menu.svg Unsupported Method
Extracting RightShift.svg Unsupported Method
Extracting Windows.svg Unsupported Method
Sub items Errors: 6
Posted: 10 Nov 2011, 19:19
by sixty
Maybe the rar file is just corrupted
Posted: 10 Nov 2011, 19:22
by 7bit
sixty wrote:Maybe the rar file is just corrupted
I always knew that Windows and corruption go well together!
Posted: 10 Nov 2011, 20:02
by Soarer
Version 9.20.1 ... "unsupported method" with RAR files - " fixed
http://sourceforge.net/projects/p7zip/f ... ip/9.20.1/
Posted: 10 Nov 2011, 20:39
by JBert
7bit wrote:Soarer wrote:...
Anyway, just get 7zip / p7zip and stop telling the other 99.99999997% of people to comply with your demands!
Write a free unrar which can unrar the latest rar files and I will never ever complain again.
Also, everybody knows that there are only 99.999835292% of all home-computers running Windows!
Do you mean free, as in money, or free, as in OSS/GPL?
This is what my version of unrar says:
UNRAR 4.00 freeware Copyright (c) 1993-2011 Alexander Roshal
Posted: 10 Nov 2011, 20:48
by 7bit
JBert wrote:7bit wrote:UNRAR 4.00 freeware Copyright (c) 1993-2011 Alexander Roshal
Freeware is not free! Freeware is dead since the early 1990s!
¡Long live free software!
And now, as anything has been said,
let's discuss the real thing:
Universal 7 units Spherical space bar
