I moved to DragonFly 2.10 over the past few days, and I tried out deduplication, to see what kind of results I would get.  The procedure is outlined below.  I'm using /home here as an example, just to reduce the amount of text pasted in. /pfs/@@-1:00004     966000640 566434576 399566064    59%    /home Move my various Hammer pseudo-file systems to version 5, which supports deduplication. # hammer version-upgrade /home 5 Issue a deduplication simulate command, to see what it guesses will be the savings: # hammer dedup-simulate /home Dedup-simulate /home: objspace 8000000000000000:0000 7fffffffffffffff:ffff pfs_id 4 Dedup-simulate /home succeeded Simulated dedup ratio = 1.22 That ratio turned out to be pretty accurate for the actual deduplication.  I didn't time it, unfortunately.  I don't know if the time taken is proportional to the amount of deduplication or the total volume of data, though I suspect the latter. # hammer dedup /home Dedup /home: objspace 8000000000000000:0000 7fffffffffffffff:ffff pfs_id 4 Dedup /home succeeded Dedup ratio = 1.22 462 GB referenced 378 GB allocated 14 MB skipped 6869 CRC collisions 0 SHA collisions 0 bigblock underflows The end result? /pfs/@@-1:00004     966000640 505887504 460113136    52%    /home That data space is shared across all file systems, and it's a 1TB disk, so it's 7%, or 70GB. I was hoping for more, but I don't have any obviously duplicated data (no local mail store, no on-disk backups), so perhaps this is normal. 70GB that I didn't have before is no bad thing, though. Incidentally, I was able to upgrade my installed software from pkgsrc-2009Q4 to pkgsrc-2011Q1 entirely using pkg_radd -u <pkgname>.  Remarkably quick and painless, though pkgin may have been able to do it even faster since it would pull from the same place.
  • Do you like the Opera browser?  Apparently all it takes is a little misspelling to confuse it with a U.S. daytime talk show host.  The "Best of Oprah emails to Opera".   (via)  Mistaken identity on the Internet is always fun.
  • Popular free software licenses, described.  (via)  One of the better, non-polemic descriptions I've seen.
  • For the opposite effect, the Free Software Foundation's license recommendations.  Somehow, the BSD license isn't even mentioned.  (via)  A commenter at the source link notes that the GNU Free Documentation License isn't even considered 'free' by Debian.  Along those lines, I've always thought that GPL licensing creates a perverse incentive to keep your software undocumented.
  • The FreeBSD and NetBSD Foundations have acquired a license for libcxxrt from PathScale, which I assume is for C++ support in conjunction with clang.  (or pcc?)  This isn't as much of an issue for DragonFly right now since we're continuing down the GCC route.
  • Temple of the Roguelike, a searchable database of roguelike games.  It's an idea that you would totally expect for this genre.  (via trevorjk on EFNet #dragonflybsd)  Also: a roguelikedev subreddit.
This new build is on x86_64, pkgsrc-2011Q1.  It's already uploaded, if you want to update.  i386 coming soon.   Several packages freeze up during build, so it's been turning into a manual process.
I managed to build openjdk7 on a DragonFly 2.9 system, and run a Minecraft server... but I can't connect to it.  Anyone want to hazard a guess as to why?  I haven't used Java much in the past few years, so I'm not sure where to troubleshoot.
One of the Google Summer of Code projects that will be valuable for DragonFly even though it isn't a DragonFly project: "Add other package formats to pkgsrc", where pkgsrc can interpret rpm, dpkg, and FreeBSD Ports files.  Anyway, the project has a Sourceforge site.
I haven't covered recent disk encryption work evenly, here, so I'll point at a recent discussion instead.  Alex Hornung mentioned a cryptsetup(8) man page that may help, as does any dm-crypt tutorial out there on the Internet.  (DragonFly has the same userland tools.)   The DragonFly installer will create encrypted disks at install time, too.
The I/O APIC is now always on unless you say otherwise.  This may not make a clear difference to you, but enabling that kernel option has always been a somewhat iffy thing; working for some configurations and not others.  Now, it's one less thing to worry about.
EuroBSDCon 2011, which is being held at Maarssen, The Netherlands, is October 6th through 9th of this year.  If you want to get a paper in, the deadline is in a week - May 30th.  Get a move on if you want to present!
This week, the links are generally fun.
Here's some recent notes on running Java on DragonFly; I may have posted something similar before, but it doesn't hurt to keep the information out there.