If you're launching a weapon and it doesn't crash into something, you're in orbit.
Anyway, I do performance modeling at work. My simulation code always has debugging symbols and all assert()'s left in (except for a few hard-hit IO libraries), because you never know when you're going to hit some data that tickles a latent bug.
Just because you use UDP doesn't mean you can't get a complete, reliable transmission. NFS and AFS both use UDP. The protocol has the same checksums on each packet as TCP, so you have some assurance that packets that you receive are okay.
What you probably mean is that UDP makes no guarantees as to whether a packet is actually delivered or not. There is no reason why an application can't implement reliable transmission itself and resend packets if it hasn't received an acknowledgement. If you don't want/need all of the "features" of TCP (congestion control, eventual delivery with no particular timing guarantees*, significant connection setup time, etc...), this might be the way to go.
* No, UDP doesn't make timing guarantees either, but your application can have greater control over a timeout that it implements.
Donno about you, but I have a lot of trouble with the buttons on my StarTac. Anything smaller would be impossible for me to use (and I don't have fat fingers, they just shake a bit).
What people need to do is make the buttons and fonts bigger so that people like me (or the baby-boomers who are hitting 55+ years nowadays) can use them.
I did actually run Win95 with 4MB of RAM on a machine that I was playing around with. The machine did not run very well, but it did boot. I remember trying to play solitare on it, but the machine would have to swap to even load in the mouse driver.:-)
The plural of virus is viruses. Virii is not a word.:-)
Similarly, whether you decide to use the right spelling does not depend on the weather. Speaking on slashdot is a privilege, not inherently a right. Bad spelling is adequate for previews, but not final submissions.
Re:They're Trying So Hard...
on
Linux Virus Alert
·
· Score: 0, Flamebait
The only way a linux virus is ever going to do damage is if
it gets into a package on a major distro's ftp and goes unnoticed.
Yes, this would work well for a binary IsFull or !IsFull reading. I actually wanted to know how many cups were in the pot (and especially when it was empty, as it is in the common case). A ping-pong ball might work better for the binary measure, though it is a little large. Calibration might be hard for anything more accurate with that setup.
The advantage of the ruler was that I only had to calibrate it once (the resistors were fixed and outside the coffee machine) and it was easy to remove for cleaning. It also had an obvious failure mode (sometimes it would read -13 cups, then you'd know there was short somewhere).
The point of this project was to have fun, of course, not to make a coffee machine that people would ever drink from. Overengineered? Probably. But it was cool to have an LED flash everytime someone hit the webserver. And hey, doesn't everyone want to know the temperature of their dorm room to within 10 degrees rankine? (yep, it reported kelvin and rankine)
That was a possibility, but I never wanted to fork out money for a webcam back then. They were more expensive than the crappy USB cameras that you see now.:-)
I like this idea. I'm just not sure where you'd mount the ball on a stick. If you mount it on the machine itself, you'll have problems getting the pot out. If you mount it on the pot, you're going to have to make it removable, so that you can clean the thing! (Yuck)
At any rate, I'm not quite sure how you would get a measurement out of this. Attach the stick to a loose potentiometer? Not to mention, the stick would have to have a useful range of movement 80 to 90 degrees in order to capture the information that you want. My guess is that it would be less accurate than the ruler, but if you just want a ballpark measurement, it might work fine.
I actually did this to my coffee machine (Winter Break, 1998). At the time, it was a Mr. Coffee 12-cup commercial coffee machine (since disposed of, pictures at: http://www.rabidpenguin.org/images/more/pic00023.j pg . The machine had a bunch of sensors attached to it, including temperature of the pot (red tape on the front), air temperature, amount of water in the pot (see the ribbon cable). Everything was attached to a Basic Stamp II, which had a serial cable to a 486 Linux webserver (mrcoffee.res.cmu.edu at the time).
It turns out that sensing the amount of water in the pot is quite difficult. If you use a scale, it has to handle heat, humidity, and steam if you put it under the pot. If you put it under the machine, you will also have plenty of water screwing up measurements because it stays in the filter. I thought about bouncing a laser diode over the surface of the water, but that never materialized. I also tried measuring the capacitance of the coffee between two places (more coffee = more conductive dielectric). That didn't work. Coffee and tea are great conductors.
Finally, I took a plastic ruler, drilled holes in it and hooked wires from a ribbon cable up to it, at a regular spacing. The coffee would short between a pin at a certain height (each pin was attached to an R2 ladder) and the ground pin at the bottom. This actually worked reasonably well! (If you could stand a ruler in your coffee pot!)
Oh, I didn't want to figure out how to write a web hit counter CGI script, so I had the stamp store the number of hits in the stamp's EEPROM! Much easier! I still have the code and the hardware lying around, though the coffee machine is long gone (last attached to a DECstation 5000/260, actually).
If you are going to use descriptive names (which I think is a fine idea), particularly like the one you mentioned, make sure the steps of the algorithm are clearly denoted. When one programmer sees an algorithm (or a maintainer looks it up in a book), they may be looking at the same algorithm, broken into different steps. There is nothing more frustrating than seeing the right thing (if you look in book A), labeled in a completely different way (because you learned it from book B).
I think one of the biggest problems is that people believe that because they named something clearly, it must automatically be clear and logical to others. More generally than just naming steps of an algorithm, this is a problem with naming commands, functions, variables, etc. I think this paper makes a strong case http://citeseer.nj.nec.com/furnas87vocabulary.html for the naming problem (yes, this is even a problem with experts in a particular field). Names are great, they don't always stand on their own. I'd highly suggest that people read the short section on "armchair" naming. I haven't seen a programmer who wasn't tempted to use this at one point or another.
Yep, I remember taking my TI-85 apart in high school and removing capacitor C9 from behind the display. Everything ran about 4 times faster! The only bad thing was that zshell quit working.:(
Scientifically proven. Sorry, I don't have the original source for this, but it was one of the few things that I actually believed from my social psych class.
I remember Dell giving out those CDs at a job fair last year. They also had a warning against putting them in the tray-type drives that were sold on their own systems at the time.
Domain monger did a similar thing to me a few weeks ago. I had my DNS handled by their servers. They claim that one of their DS3's was nailed by a backhoe, so they just made all hosts under my domain (registered or not) resolve to one of their ads webservers.
Why they couldn't make it resolve to a server saying "we're having technical problems, this is not a sales pitch" is beyond me. Needless to say, they got lots of ssh connections to that box while I tried to figure out what was happening (and tried to remember my IP addresses).
I have heard rumors that one group in the energy-aware computing class here at CMU is working on making a speedstep patch that actually works while you're up and running. Apparently the code from Intel is out there, it's just broken and needs to be fixed! Check back around december...:)
Ditto, I can get 6 hours on my Inspiron 8100 (two batteries) with the screen on and having it play an internet radio station with an editor (Xemacs for win32) or excel in use, along with an X server and a wireless card.
As far as I know, linux's powerstep support is broken at this point, so you'd be running at full tilt (I haven't had the time to do a quantitative analysis with the processor at this setting, for obvious reasons). Recently I have gotten into the bad habit of not plugging the system in after getting back home. I usually don't notice that oversight for a few hours.:)
Don't forget WQED (classical music, public radio), which has managed to survive so far and still bring good programming. I also listen to WDUQ (Duquesne's jazz station/NPR feed).
A while back, Philadelphia had a public classical station, too. Someone bought it (possibly Clear Channel) and turned it into pop, then R&B or something and now it has turned back into top 40's. Temple's Jazz station picked up the classical during day hours, but they really don't understand classical music (they used to be much better at jazz, too).
Slashdot Mirror
Insight of the day...
If you're launching a weapon and it doesn't crash into something, you're in orbit.
Anyway, I do performance modeling at work. My simulation code always has debugging symbols and all assert()'s left in (except for a few hard-hit IO libraries), because you never know when you're going to hit some data that tickles a latent bug.
Just because you use UDP doesn't mean you can't get a complete, reliable transmission. NFS and AFS both use UDP. The protocol has the same checksums on each packet as TCP, so you have some assurance that packets that you receive are okay.
What you probably mean is that UDP makes no guarantees as to whether a packet is actually delivered or not. There is no reason why an application can't implement reliable transmission itself and resend packets if it hasn't received an acknowledgement. If you don't want/need all of the "features" of TCP (congestion control, eventual delivery with no particular timing guarantees*, significant connection setup time, etc...), this might be the way to go.
* No, UDP doesn't make timing guarantees either, but your application can have greater control over a timeout that it implements.
The DoJ is doing its darnedest to break up the unbreakable MSFT.
What people need to do is make the buttons and fonts bigger so that people like me (or the baby-boomers who are hitting 55+ years nowadays) can use them.
Surely you jest. Or you mean kb/s. Or maybe you're an evil daemon from the future, paid by the German tourist board, sent back to taunt us.
I did actually run Win95 with 4MB of RAM on a machine that I was playing around with. The machine did not run very well, but it did boot. I remember trying to play solitare on it, but the machine would have to swap to even load in the mouse driver. :-)
You'd think that with the process shrink, they'd at least make the L1 data cache a little bit larger. 8kB is surprisingly small.
Similarly, whether you decide to use the right spelling does not depend on the weather. Speaking on slashdot is a privilege, not inherently a right. Bad spelling is adequate for previews, but not final submissions.
Kinda like GNOME?
The advantage of the ruler was that I only had to calibrate it once (the resistors were fixed and outside the coffee machine) and it was easy to remove for cleaning. It also had an obvious failure mode (sometimes it would read -13 cups, then you'd know there was short somewhere).
The point of this project was to have fun, of course, not to make a coffee machine that people would ever drink from. Overengineered? Probably. But it was cool to have an LED flash everytime someone hit the webserver. And hey, doesn't everyone want to know the temperature of their dorm room to within 10 degrees rankine? (yep, it reported kelvin and rankine)
That was a possibility, but I never wanted to fork out money for a webcam back then. They were more expensive than the crappy USB cameras that you see now. :-)
At any rate, I'm not quite sure how you would get a measurement out of this. Attach the stick to a loose potentiometer? Not to mention, the stick would have to have a useful range of movement 80 to 90 degrees in order to capture the information that you want. My guess is that it would be less accurate than the ruler, but if you just want a ballpark measurement, it might work fine.
It turns out that sensing the amount of water in the pot is quite difficult. If you use a scale, it has to handle heat, humidity, and steam if you put it under the pot. If you put it under the machine, you will also have plenty of water screwing up measurements because it stays in the filter. I thought about bouncing a laser diode over the surface of the water, but that never materialized. I also tried measuring the capacitance of the coffee between two places (more coffee = more conductive dielectric). That didn't work. Coffee and tea are great conductors.
Finally, I took a plastic ruler, drilled holes in it and hooked wires from a ribbon cable up to it, at a regular spacing. The coffee would short between a pin at a certain height (each pin was attached to an R2 ladder) and the ground pin at the bottom. This actually worked reasonably well! (If you could stand a ruler in your coffee pot!)
Oh, I didn't want to figure out how to write a web hit counter CGI script, so I had the stamp store the number of hits in the stamp's EEPROM! Much easier! I still have the code and the hardware lying around, though the coffee machine is long gone (last attached to a DECstation 5000/260, actually).
I think one of the biggest problems is that people believe that because they named something clearly, it must automatically be clear and logical to others. More generally than just naming steps of an algorithm, this is a problem with naming commands, functions, variables, etc. I think this paper makes a strong case http://citeseer.nj.nec.com/furnas87vocabulary.html for the naming problem (yes, this is even a problem with experts in a particular field). Names are great, they don't always stand on their own. I'd highly suggest that people read the short section on "armchair" naming. I haven't seen a programmer who wasn't tempted to use this at one point or another.
Yep, I remember taking my TI-85 apart in high school and removing capacitor C9 from behind the display. Everything ran about 4 times faster! The only bad thing was that zshell quit working. :(
Scientifically proven. Sorry, I don't have the original source for this, but it was one of the few things that I actually believed from my social psych class.
I remember Dell giving out those CDs at a job fair last year. They also had a warning against putting them in the tray-type drives that were sold on their own systems at the time.
Domain monger did a similar thing to me a few weeks ago. I had my DNS handled by their servers. They claim that one of their DS3's was nailed by a backhoe, so they just made all hosts under my domain (registered or not) resolve to one of their ads webservers.
Why they couldn't make it resolve to a server saying "we're having technical problems, this is not a sales pitch" is beyond me. Needless to say, they got lots of ssh connections to that box while I tried to figure out what was happening (and tried to remember my IP addresses).
2600Hz, maybe. I doubt the crappy verizon payphones could pick up 2.6MHz "tones". Heck, they barely pick up anything except my pocket change.
Alright, I give up. What's a "gang adapter"?
- Joe Ignorant American
I have heard rumors that one group in the energy-aware computing class here at CMU is working on making a speedstep patch that actually works while you're up and running. Apparently the code from Intel is out there, it's just broken and needs to be fixed! Check back around december... :)
As far as I know, linux's powerstep support is broken at this point, so you'd be running at full tilt (I haven't had the time to do a quantitative analysis with the processor at this setting, for obvious reasons). Recently I have gotten into the bad habit of not plugging the system in after getting back home. I usually don't notice that oversight for a few hours. :)
This isn't too far-fetched. Four years ago I had my coffee machine wired up to a webserver.
Achieves leadership?
My PHB has all that covered. [back to slinging code]
A while back, Philadelphia had a public classical station, too. Someone bought it (possibly Clear Channel) and turned it into pop, then R&B or something and now it has turned back into top 40's. Temple's Jazz station picked up the classical during day hours, but they really don't understand classical music (they used to be much better at jazz, too).