On Dec 5, 2010, at 9:55 PM, Brett Cannon wrote:
Well, is it more popular because that is just what people are used to downloading or the first download link on the web page? Or is it because people fundamentally prefer tgz files over tar.bz2?
I prefer tgz over tar.bz2 because my fingers are more used to typing gz* than bz*, and because it's more likely that gzip will be installed than bzip. But my habits were formed before bzip was even available.
I have chosen bzip over gzip in cases where I know that download bandwidth was limited but otherwise I use gzip.
Plus, Python comes with a gzip module. ;)
Are there actual platforms that can't handle tar.bz2 but can handle tgz?
I can test this tomorrow when I visit my client and type "bzip" into a box there, but I think the answer is "yes." This is a 3-4 year old Linux box where I had to install a number of packages just to get it to state where I could compile Emacs 23.x, since their package installer doesn't have a new enough Emacs version.
Short version: most of the users log into the Linux box to run pre-compiled chemistry applications. They aren't doing development on the machines.
If Python was only available in bzip then I would have to install bzip myself - which isn't hard - while I grumble that it's more work for me for little savings. After all, in these cases I'm at a large pharmaceutical company with plenty of bandwidth, so the savings of a few MB won't be noticeable.
They sure aren't going to have xz.
So, drop .tar.gz and I can still handle it.
Personally I don't know why we have both tgz and tar.bz2 other than tradition. I say trim it down to tar.bz2 for portability and move on to using a ustar-based tar.xz to be cutting edge and minimize download size overall while making it the first download option to make sure people notice it.
While I would say to drop the bz2 and make it an xz instead. *shrug* it's no big deal either which way.
If this is something you want to figure out, there's no need for a poll. This is near ideal case for A/B testing. Swap the two lines now and see what changes. And watch the referrer logs to identify which downloads come from that page.
Before today I had never even heard of .xz files. For others who haven't heard of it, it's based on the LZMA2 algorithm, which is a slight improvement on the LZMA algorithm which 7zip uses. It's been for about 2 years, and so I'm surprised to see that it's part of the GNU coreutils already.
Here's a short read about the history http://linuxgazette.net/162/lindholm.html with some numbers as well. It looks like the compression time is a lot longer than gzip. This page http://stephane.lesimple.fr/wiki/blog/lzop_vs_compress_vs_gzip_vs_bzip2_vs_l... recommends gzip if you want compression speed, and xz if you want smaller size.
Andrew
dalke@dalkescientific.com