Lazy Reading for 2011/06/05

Short but good this week.

  • I always enjoy seeing other people’s window configs, even if I don’t use them.
  • The CCBY license is very similar to the BSD license – and there’s some big institutions using it.  That is good news for everyone.
  • I linked to telehack before, but I didn’t realize how huge it was.  There’s 25,000 virtual hosts in there, recreated from history, complete with realistic user lists.  You can ‘hack’ into hosts, or run games and BASIC files.  (hammurabi!)  It even recreates early USENET.  Read the description of what to do – it gets really interesting about halfway down.   It’s an Internet Simulation, if ever there was one.  (via)
  • Remember I posted earlier this week about my results with deduplication?  I had about a 7% gain of the disk.  As time has gone on and the Hammer reblocker was able to work overnight, I’m now up to a gain of 10%.  Neat!
  • Also: I got Minecraft working (as a server) on DragonFly.  See the comments on my original it’s-almost-working post.
  • RAS Syndrome: Recursive Acronym Syndrome Syndrome.  For anyone who has typed “GNU”.  (via)
Trying out deduplication

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.

Lazy Reading for 2011/05/29

Whee!

  • 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.