[ruby-core:30364] Re: [Feature #1478] Ruby archive

Hi,

On 22 May 2010 01:44, Caleb Clausen <[e-mail]> wrote:
> I'm not a big fan of .zip either, but give it its due.
>
> Zip has the advantage that you can 'seek' to arbitrary files within
> the archive without needing to decompress all the other files that
> come before it. That's not true of gzipped tar files.....
>
> Because each member of a zip file is a compressed separately. But this
> same design decision is why .tar.gz compresses better than .zip, given
> the same collection of files.
>
What about LZMA (p7zip, xz) ?

From my experience it's far better in size than .zip and .tar.{gz,bz2},
and it has the ability to get one file at a time.

The downside, is, I suppose, the speed/computation for compressing/extracting.

Let's see a little on Ruby's source (I could not get xz working on OSX):
(format, size, compression time, extraction time, relative size to
original, Mo compressed/s, Mo extracted/s)
fmt   size   ctime xtime  psize   Mc/s Mx/s
7za  5476 14.7s 7.8s 13.01%  2.86  5.39
bz2  6792  8.7s  3.6s 16.14%  4.84  11.69
gz    8252  3.0s  4.0s 19.61% 14.03 10.52

I personally prefer a little slower compression/extraction with a low
size, as it make easier downloads.

Regards,
B.D.