CPAN is much smaller, but let's get it below 7 Gb!
At the end of last week, I sent mail to all CPAN authors letting them know that they could delete older distributions from author directories. CPAN is pretty large: last week it was almost 8 GB, and today it's almost down to 7 GB. That puts the Schwartz Factor at about 1/7th. We can do better.
It's not the size that's the problem so much: disk is cheap (still, no need to waste it). The more distributions CPAN stores, the more the masters need to check when a mirror wants to rsync. For the most part, mirrors only need to delete the files that disappeared and want the ones that appeared. The other files (aside from the PAUSE files such as CHECKSUMS) should not have changed. The
rsync program doesn't know anything special about CPAN though, so it still does all its work.
Tim Bunce, inadvertantly I think, started a long thread about possibly automating the PAUSE purging process. There are all sorts of technical suggestions and fights about filesystems. While they figure all that out, though, you can help those mirrors by cleaning up the ancient distributions in your PAUSE directory.
And, if you didn't get my email, sent individually to every CPAN author (asking the Perl NOC first, of course), you might also take the opportunity to update your PAUSE profile.
If you've already done your bit to make PAUSE smaller, you can still help by spreading the word. I'm sure a lot of CPAN authors didn't read my mail. :)