Using xz by default for compression

[Rainer Müller]

On 2015-01-26 11:24, Ryan Schmidt wrote:
> Upon further investigation, hfscompression uses zlib, and has further
> optimizations for small files:
> 
> http://wiki.sleuthkit.org/index.php?title=HFS#HFS.2B_File_Compression
>
>  Re-reading the ticket above, it sounds like it's talking about the
> files that get installed when a port is activated. Yes,
> hfscompression would benefit that situation and we should do it, if
> all the concerns in the ticket have been addressed.

Yes, this is for the installed files, which are currently not compressed
at all. Applying compression on uncompressed files will reduce the disk
space requirement more than using a different algorithm for already
compressed files.

> Archives, however, will not benefit from being zlib-compressed; using
> hfscompression on our current bz2 archives would not save any space,
> and using hfscompression on uncompressed tar archives would take more
> space than our current bz2 archives.

I concur that compressing already compressed files would not have any
benefit.

> So yes, we should pursue hfscompression, but it is orthogonal to the
> issue discussed in this email thread.

Maybe I should have changed the topic when introducing this. Sorry for
the confusion. It is kind of orthogonal, but the goal of both approaches
is to reduce disk usage. I just wanted to give a pointer to an existing
patch which would require less work to achieve that.

Rainer