[tex-live] Proposal for distribution snapshots

[Nelson H. F. Beebe]

Given the recent issues with getting a working (and possible
historical) copy of TeXware out of the repository, and given that only
a core of developers has access to the revision control system, how
about setting up a cron job that, say, at midnight UTC, created a
daily snapshot of the entire source archive in .tar.gz or .tar.bz2
form, with a timestamp in ISO 8601 format as part of its name, such as
tex-live-2004-02-07.tar.bz2, with those snapshots accessible to anyone
via normal FTP and HTTP?

The texlive-2003-9/texmf/source tree takes 63MB, so each compressed
snapshot would be about 20MB.  To verify that, I ran this test on my
1.05GHz Sun Sun Blade 2000:

	% cd /home/0072/texlive-2003-9/

	% time env BZIP2=-9 tar cfj /tmp/foo.tar.bz2 texmf/source
	38.14u 4.58s 5:16.33 13.5%

	% time env GZIP=-9 tar cfz /tmp/foo.tar.gz texmf/source
	25.72u 3.11s 0:40.58 71.0%

	% time zip -rq /tmp/foo.zip texmf/source
	12.81u 1.22s 0:23.37 60.0%

	% ls -l /tmp/foo.tar.*
	-rw-rw-r--  1 beebe staff 13646720 Feb  7 05:55 /tmp/foo.tar.bz2
	-rw-rw-r--  1 beebe staff 16344671 Feb  7 05:55 /tmp/foo.tar.gz
	-rw-rw-r--  1 beebe staff 18644242 Feb  7 06:04 /tmp/foo.zip

We could make 78 snapshots/GB in bz2 format, 65/GB in .gz format, or
57/GB in .zip format.

The /home/ftp/texlive/Source tree on tug.org currently has 16GB free,
so I don't see that the required space would be a problem: we could
keep a year's worth of snapshots in 5GB.

Also, the ready availability of snapshots might encourage other sites
to mirror them, giving valuable data protection and distribution.

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- Nelson H. F. Beebe                    Tel: +1 801 581 5254                  -
- University of Utah                    FAX: +1 801 581 4148                  -
- Department of Mathematics, 110 LCB    Internet e-mail: beebe at math.utah.edu  -
- 155 S 1400 E RM 233                       beebe at acm.org  beebe at computer.org -
- Salt Lake City, UT 84112-0090, USA    URL: http://www.math.utah.edu/~beebe  -
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