Friday, July 28, 2006
We got one of our teenagers an MP3 player for her birthday. Based on reviews and such, I'm pretty excited about this one. It's the SanDisk Sansa e250. The price wasn't outrageous and the functionality is just right.
Navigation is with a mechanical wheel, four buttons and a center button. It has the requisite blue LED lighting effects which looks (the requisite) cool. The screen is large, nicely hi-res and bright. A battery charge is claimed to last about 20 hours. It has a built-in FM radio (which you can record from of course), video player, and picture viewer. You have to convert video and images into a special format before loading them onto the player. It works with WMV and MP3 files (and many others through conversion), and it's compatible with subscription services like Yahoo and Napster. It's nicely small but very cool. Also the plastic front is said by reviewers to be a much harder plastic than that used by ipods and others which scratch easily. The back is metal.
You can change the modes it uses when plugging it in so it either talks to Windows Media Player or it just looks like a USB disk/memory device. I used the latter mode, plugged it into an Ubuntu machine and the mounted disk popped up on the desktop. It was trivially simple to drop music folders into it. (You can include album-cover art, too, but those images have to be converted as mentioned above). When you unmount the USB device it rebuilds it's music database automatically. It also recharges via the USB connector.
What I really like is that there's a microSD slot so you can add more memory (we got the 2-GB version but there are 4-GB and 6-GB). As microSD's get larger this provides a way to grow the player's capacity. Also, and this is very important to me, the Li-Ion battery is user-replaceable!
The main problem now is everyone in my house wants one instead of the lower-cost MP3 players they have now. My problem is that I'm last in the line for MP3 players, probably after the dog…
Wednesday, July 26, 2006
The kernel vulnerability that has been used for this compromise is referenced as CVE-2006-2451. It only exists in the Linux kernel 2.6.13 up to versions before 184.108.40.206, and 2.6.16 before 220.127.116.11. The bug allows a local user to gain root privileges via the PR_SET_DUMPABLE argument of the prctl function and a program that causes a core dump file to be created in a directory for which the user does not have permissions.
The current stable release, Debian GNU/Linux 3.1 alias 'sarge', contains Linux 2.6.8 and is thus not affected by this problem. The compromised server ran Linux 18.104.22.168.
Monday, July 24, 2006
To get it all working required setting up some details, things like copying over my book marks from Firefox and address book from Thunderbird.
One thing I had a terrible time with was getting a file manager icon on the top icon bar. On Hoary it was an app called File Manager and it was simple to add. On Dapper it's actually Nautilus and I finally had to create a customer app launcher to put it there. The binary is nautilus.
Another annoyance from this morning is that, when in Firefox and I Save Image..., Firefox insisted on saving a PNG image as a .cgi file. That's a little messed up and different from the behaviour of Firefox on Hoary. I'm sure it's a trivial fix and it might be a decision vs. just an oversight of some sort, but I won't take the time to dig down into what's going on.
Sunday, July 23, 2006
Penn State computer science professor Max Fomitchev explains that computing has evolved in a spiral pattern from a centralized model to a distributed model that retains some aspects of centralized computing. Single-task PC operating systems (OSes) evolved into multitasking OSes to make the most of increasing CPU power, and the introduction of the graphical user interface at the same time reduced CPU performance and fueled demands for even more efficiencies.
“The role of CPU performance is definitely waning, and if a radical new technology fails to materialize quickly we will be compelled to write more efficient code for power consumption costs and reasons,” Fomitchev writes.
Slow, bloated software entails higher costs in terms of both direct and indirect power consumption, and the author reasons that code optimization will likely involve the replacement of blade server racks with microblade server racks where every microblade executes a dedicated task and thus eats up less power. The collective number of microblades should also far outnumber initial “macro” blades.
Fully isolating software components should enhance the system's robustness thanks to the potential of real-time component hot-swap or upgrade and the total removal of software installation, implementation, and patch conflicts. The likelihood of this happening is reliant on the factor of energy costs, which directly feeds into the factor of code optimization efficiency.
Thursday, July 13, 2006
Subject: STS-121 Discovery -- Space Shuttle Mission
Date: Tue, 11 Jul 2006 09:24:22 -0400
Booster cam on the recent shuttle launch. Somewhere past 3 minutes, the booster separates and falls back to earth.
Sometime around 6.30 minutes, the chute stabilzes the descent and at 7.30 minutes the booster hits the water.
Curt also sends this link. This video is backward-facing so you can see the trail and water during the ascent and you are looking down at the clouds and water during the descent. This is what it would be like to ride on the outside of the shuttle!
REAL Video- 12+ minsThese are additional videos pointed to in Curt's note.
/rm/etouchsyst2.download .akamai.com/18355/real.nasa -global/sts-121/right_forward _srb.ram
1:30 Good view of Cape
3:00 SRB sep & tumble (blue, black, blue, black...)
5:30 Parachute must've deployed (no more black--all blue)
Launch, SRB sep, descent, splashdown
_pages/shuttle/main/Shuttle _Multimedia_Collection_archive _1.html
Wednesday, July 12, 2006
Dsmc was specifically looking for libstdc++-libc6.2-2.so.3. It turns out this library is in some compatibility rpms. Actually I'm not sure which one did the trick since I installed both, in this order.
Monday, July 10, 2006
This article at Security Focus has a nice intro and covers file encryption.
Here are some examples of so-called “volume encryptors”.
- Secure File System (SFS)
- Linux CryptoAPI
Saturday, July 08, 2006
Friday, July 07, 2006
Thursday, July 06, 2006
The actual number of bytes (or whatever) will be represented by N.
Generally, all possible meanings can unfortunately be expressed by:
N = 103n 210m P
where n + m = k.
For the symbols, k has the following values.
|K||k = 1|
|M||k = 2|
|G||k = 3|
|T||k = 4|
Hopefully, n = 0 and m = k but, sadly, that frequently isn't the case.
I think the best and most unambiguous solution is n = m = k = 0 and N = P!
Wednesday, July 05, 2006
I generally think of process threads as more than one program counter executing in a shared address space. If you have two CPUs, e.g., then each of two threads can execute on each of the two CPUs.
Typically with one CPU it's necessary to schedule instructions from a particular thread on the CPU, then switch to the other thread at some appropriate point.
Hyperthreading is a similar idea handled inside the CPU. Instructions from two streams are decoded into microcode instructions (uops). Where possible different sets of microcode are run “simultaneously” on different execution units of the processor. When this simultaneous scheduling of microcode works, you get something like the performance of two CPUs minus the overhead involved in scheduling and management of two logical CPUs. When one set of microcode has to wait on another, then you are back down to single-CPU performance (and still minus the management overhead, thus the penalty for hyperthreading).
I found a nice article that explains hyperthreading at a useable level of detail.
One of my family showed it to me this weekend and it's interesting. You don't have to focus on the game continuously but set operations in motion that continue while you may not even be logged on. The technical organization “feels” a little like Starcraft, but without the point-and-click look and feel.
It's the kind of game a system administrator, or perhaps even a manger, could love.
I recently switched from Yahoo to Gmail for personal email after Yahoo just became unacceptably slow and apparently less effective at spam handling.
Gmail for my Domain is excellent so far. The management interface allows one to create accounts, set and reset passwords (and force the user to change them), set up aliases, lists (based on the set of users in the domain) and monitor quota usage.
I'm limited to the number of email addresses I requested in my application.
I also confirmed last night that you can share Google Calendars with users in the domain since it lets you specify the full email address of someone you want to share a calendar with. It all just works!
Tuesday, July 04, 2006
This is combined with deciding that my 15-in wide screen Inspiron 8600 is too large for some uses. I really like it for desktop work, conference room work, and working at home when not in my office at home, is really great! But it's a bit too big to haul into Starbucks and I find I tire of dragging it into the office every day. (Typically I don't since I use an Ubuntu system for most of my desktop OS work).
Finally, OS-X has a particular attraction since it bears so much of it's ancestral NeXT OS which I knew well and loved dearly.
So I've been thinking about smaller and lighter wireless devices. But playing with them briefly at the ~Apple store embedded in Fry's, I found the new Macbook and older Powerbook harder to use than the Windows machines. And the Windows machines can (potentially) run Ubuntu, which I generally prefer. The Windows laptops I tried were much snappier. Granted this is typically a matter of tuning and such but I looked at the machine specs and they were about the same. I really, really, really prefer more mouse buttons. (I like three buttons better than two which I like better than one!).
(By the way, I decided the coolest laptop I've seen recently is the Vaio SZ, but it's about as expensive as a Mac laptop! Note however the focus here is on screen, keyboard, and portability).
So this morning this article in Slashdot pops up on the radar about switching from Mac to Ubuntu.
Sunday, July 02, 2006
The original Allman Brothers Band at Filmore East, Whipping Post Part 1 and Part2.
A Stanley Clarke solo on upright bass that is very much like the performance that my daughter and I saw at Symphony Hall here in Atlanta last Christmas, when he played with Jean Luc Ponty and Bela Fleck as Trio. I've seen him perform twice before, once with the original Return to Forever (!) and a second time sitting on the edge of the stage at the Fox in Atlanta just playing his electric bass for a while. But I was completely blown away by the Trio concert.
Here's an older video of Stanley Clarke on upright bass.
Speaking of Return To Forever, here's The Magician by the original band!
And if you've never seen Michael Hedges (1953--1997) play, these are some of my favorite videos of him “reinventing the guitar.”
Take a Pebble that really show off the greatest progressive rock group of the 70s. All are from around 1970.
- First version, very similar to the album (Part 1 and Part 2)
- Second on Beat Club, very nice video (Part 1 and Part 2)
- Third version, excellent piano improv by Keith Emerson