emergency file server cleanup

[Matias A. Fonzo]

El Tue, 23 Sep 2014 02:23:43 -0300
Alexandre Oliva <lxoliva en fsfla.org> escribió:
> Hello, Matias,
> 
> On Sep 18, 2014, "Matias A. Fonzo" <selk en dragora.org> wrote:
> 
> > Have you considered to use sourceforge as alternative?. It has
> > mirrors around the world.
>  
> Not really.  But how would it have helped?  I surely wouldn't entrust
> the primary copy of the source tarballs to it, so I'd have to keep
> them on our server anyway...

Of course not. The good thing is that SourceForge has a network of
mirrors which represents availability around the world. Even if
SourceForge is down or are prohibiting access to other countries. You
would have a copy somewhere.

> > Why? Lzip can compress more than xz with a bit of tuning via
> > --options.
> 
> Maybe it can, but when I compared the sizes of the files to decide
> which one to keep, .xz files were consistently (if slightly) smaller
> than .lz ones.
> 
> Maybe I'm not using the best options to compress tarballs, vcdiffs and
> xdeltas with lzip.  Suggestions are certainly welcome.

Probably `lzip -m64 -s64MiB' should be enough. This is equal to the
values of xz (match-length and dictionary size). Of course, this will
increase the memory usage in the decompression, because the dictionary
size has been incremented. In any case, consumes less memory than xz:

http://mattmahoney.net/dc/text.html (See the Ranking)
 
> > And it is not forcing users to possess a lot of memory to
> > decompress .xz.
> 
> That is a point I was not aware of, so I had not taken into account.
> 
> > Lzip was designed for long-term archiving, having a
> > tool to recover corrupt files.
> 
> I very much doubt it could recover corrupt files to the point that the
> original signature would match, because that would require a lot of
> redundancy to be added, which is the opposite of what a compressor is
> supposed to do.  And if the original signature doesn't match, I
> wouldn't trust the result, especially given that we have alternate
> paths to obtain the tarballs.

I'm not the right person to answer. I think Antonio is subscribed to
the list, he can give the details.
 
> > Ideal for linux-libre, especially because
> > it is under the GPL.
> 
> Yup, lzip remains the promoted compression format in the GNU
> Linux-libre Free Software Directory page.
> 
> Thanks for your feedback and for educating me on another aspect in
> which lzip is superior,
> 

Thanks for linux-libre.

Take care,
Matias