Fresh from BSDCan 2011, an interview with Ingo Schwartze and Kristaps Dzonsons, mostly about mdocml. (Which is already present in DragonFly.)
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.
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.
If you follow this thread, it has some discussion on how to handle a multi-disk setup and Hammer. If a disk is going bad, you can try mirroring, though you have to be careful how your pseudo-file systems are set up.
The SMP option is now in the GENERIC kernel config. This means you’ll have a SMP-capable kernel even on an uniprocessor machine, unless you configure a special kernel.
Apparently the mail(1) and battlestar(6) source code caused a problem when checked out onto a NTFS volume. Sascha Wildner fixed it, and Alexander Polakov found an explanation as to why. How long has this problem been around? Well, look at the email addresses at the end of the man page for battlestar(6), for instance, or guess how long mail(1) has been around…
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.
This week, the links are generally fun.
- Hey, can this work on BSD? Cause this. (yeah, I know, hype.)
- Michael Lucas has a summary of his experience at BSDCan 2011. His third point – anyone can experiment and publish results – is something I’d like to see. I love graphs, and I love being able to see quantifiable results.
- The many slides for ’10 years of pf’, also from BSDCan 2011, are online. (via) The background images are entertaining, though it’s using that font. Slide 78 mentions that other BSDs have much older versions of pf. I think DragonFly’s running the newest old version of any of them, actually, though the slide doesn’t mention it.
- There’s Gnome people saying “Ignore everything that isn’t Linux“. No, wait, it’s not that bad!
- The history of the computer mouse. Something I’d always heard about, but not with this detail.
- Git aliases. I don’t think it’ll save you hours of your life as the author claims, but it may be handy.
- How to build your own gaming PC. The author went for funny and true, rather than the multipage exposition of out-of-date numbers and graphs that usually make up these articles.
- Where the octothorpe came from. It has to do with Unix and telephones, which are close to the same thing if you go back far enough.
- Speaking of Unix-ish stuff, here’s an interview with Ken Thompson, who recently won the Japan Prize for the creation of Unix, along with Dennis Richie. (via) Yes, it’s their fault!
- “First was viruses, second was malware, third is facebook.“
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.
I posted something about this before, but now it’s definite: bleeding-edge users of DragonFly can boot a multiprocessor kernel on a single-processor machine.
If you’ve ever wanted to really make sure of all the network interfaces supported on your DragonFly system, you can create an exhaustive (and exhausting) list.