We all know the answer: [Linux] is a kernel, or a microkernel to be more precise, which combined with the GNU macrokernel is an entire operating system.
I guess we all know the answer except you.:-)
Linux is a kernel, but is not a microkernel: it is a monolithic kernel. GNU+Linux makes an operating system, but GNU is not a "macrokernel" or any kind of kernel for that matter.
Again, apologies for not repeating the slashbot "party line," but I guess I will just have to take a chance with the karma.
No, actually, the grandparent article was right (though he was a bit careless with the math). Think of this: how quickly would a bowling ball with the mass of Jupiter fall at (through?) the surface of Earth?
Certainly, all objects fall at the same rate at the surface of the earth. The force involved is given by:
F = G m1 m2 / r
But F=ma, so a=F/m. That means that the mass cancels; for instance, for m1, the acceleration due to gravity equals G m2 / r. So, each body's acceleration is independent of its own mass, but is proportional the other object's mass.
So, consider the feather and hammer. While the feather accelerates toward Earth at 9.8m/s, the Earth and everything on it accelerates toward the feather at a negligible rate. Same with the hammer. Result: the observed acceleration for both objects is equal.
However, consider our Jupiter-mass bowling ball. While the bowling ball accelerates toward Earth just like everything else at 9.8m/s, the Earth falls toward the bowling ball at about 318 times that rate, for an overall attraction of over 3100m/s!
(Actually, the situation would be quite a bit more complicated than this because of the tremendous tidal forces involved, but you get the idea...)
Damn, I was just about to post an article with exactly that first sentence.
The one other thing I'd add is that I can't believe these people are dumb enough to try to force adds on people who don't want to watch them. How is that going to sell anything?
This "human eye" thing is bull. Under some circumstances, I can tell the difference between 72Hz and 100Hz, and I'm pretty sure I have human eyes.
There are at least two reasons that higher is better:
1. Interference with fluorescent bulbs. Your ambient lighting might have an imperceptible variation in brightness at a frequency slightly different from your refresh rate. When that happens, it is the difference between the two frequencies that you perceive as flicker.
2. Motion blur. Things that move on a computer screen have no motion blur: they are a series of static images. (Well, some high-end video cards do motion blur I think.) Moving images with no motion blur look very strange and sometimes confusing, and appear to flicker. (An example of this is the opening battle from Gladiator, in which motion blur was reduced to enhance the impression of chaos.) One way to simulate motion blur is to have tons of frames per second. For instance, if you have 5 times more FPS than your eye can perceive, then each five frames will effectively blur together, creating a more natural-looking motion with less flicker.
I'm sure there are more effects I haven't thought of, but you get the idea: it's not just about having enough frames to fool the eye. For #1, the key is not only high frame rate, but a frame rate sufficiently different from that of your ambient lighting (and its harmonics, I guess). For #2, the higher the frame rate the better: there is no limit. Fast-moving animations will always benefit from more FPS.
The "turtles all the way down" reference is from a Brief History of Time by Stephen Hawking. You should read it. I was referring to any theory which simply begs the question. For instance, how did life evolve? Some answer that life didn't evolve on Earth, but rather came here from another planet. That simply begs the question, since it assumes that life already existed.
So, if you want to stick your head in the sand, you can say the universe began when the previous one ended. But doesn't that leave us with the question of how this infinite sequence of expanding and contracting universes came to be?
Thus, to me, the question of whether the universe is alternately expanding and contracting is mildly interesting, but not all that fundamental.
Bah. This is just another form of the "turtles all the way down" view of the world. If it's true, it just raises the question of how/when/why the whole lot started pulsating in the first place.
They are available, but 4K pages are still supported, which is what requires the 4-level page tables.
Plus, it seems to me that 4M is too big for a lot of work. Having to page out entire 4M chunks every time paging occurs would kill performance. With today's hard drives, the delay to write 4M to disk is still observable by humans.
I have no experience with 4M pages, but it seems to me that they are not a general solution.
One thing that worries me about x86-64 is the page tables. They're 4 levels deep, and that still only gives a 48-bit address space. They stick with 4k pages. I guess they had to do it for backward compatibility, but to me this is clearly not the best approach.
Though, IA-64 is pretty questionable too. The VLIW aspect is cool, but the compilers are a nightmare. Nobody knows how to write compilers to take advantage of speculative execution, for one thing.
I'm not familiar with any other 64-bit architectures, but surely they're better than both of these?
I think the current state of affairs is that Jupiter is a planet because it does not do any fusion, and Pluto is a planet because everyone likes it too much to cast it back into the Cuiper belt.
But I have to say that when I first heard that a Cuiper belt object had a moon, my first thought was "hey, that's the second one after Pluto".
You object to the "with it"? Seems ok to me. Removing it changes the meaning of the phrase.
Personally I would totally rewrite this phrase, but I wanted to make minimize the change. That aside, my favourite is the one someone already posted: "Creative includes some closed-source software that allows them to sneak in per-call charges,..."
Creative has some closed source software with it that they manage to sneak per call charges in with,...
Wow, that's quite the phrase you have there. Let me give a suggestion: "Creative has some closed-source software with it that allows them to sneak in per-call charges,...".
Slashdot Mirror
Linux is a kernel, but is not a microkernel: it is a monolithic kernel. GNU+Linux makes an operating system, but GNU is not a "macrokernel" or any kind of kernel for that matter.
Oh please. You're a real freedom fighter.If you don't relax fast enough, they should use those electrodes to give you electrical shocks as punishment.
Certainly, all objects fall at the same rate at the surface of the earth. The force involved is given by:
But F=ma, so a=F/m. That means that the mass cancels; for instance, for m1, the acceleration due to gravity equals G m2 / r. So, each body's acceleration is independent of its own mass, but is proportional the other object's mass.So, consider the feather and hammer. While the feather accelerates toward Earth at 9.8m/s, the Earth and everything on it accelerates toward the feather at a negligible rate. Same with the hammer. Result: the observed acceleration for both objects is equal.
However, consider our Jupiter-mass bowling ball. While the bowling ball accelerates toward Earth just like everything else at 9.8m/s, the Earth falls toward the bowling ball at about 318 times that rate, for an overall attraction of over 3100m/s!
(Actually, the situation would be quite a bit more complicated than this because of the tremendous tidal forces involved, but you get the idea...)
I think that's the opposite of where things are going. We'll see more and more CPUs on a single chip, along with great gobs of ram.
What are you, a broken record?
If my company allots X sick days, and I use one for Star Wars, then what happens if I'm then sick for X days?
That's only if you believe that attending Star Wars makes someone less likely to get the flu. Otherwise, they'll take time off for each.
That sounds like a challenge. Who can be the first to make a Unix distro with no shell?
The one other thing I'd add is that I can't believe these people are dumb enough to try to force adds on people who don't want to watch them. How is that going to sell anything?
This "human eye" thing is bull. Under some circumstances, I can tell the difference between 72Hz and 100Hz, and I'm pretty sure I have human eyes.
There are at least two reasons that higher is better:
1. Interference with fluorescent bulbs. Your ambient lighting might have an imperceptible variation in brightness at a frequency slightly different from your refresh rate. When that happens, it is the difference between the two frequencies that you perceive as flicker.
2. Motion blur. Things that move on a computer screen have no motion blur: they are a series of static images. (Well, some high-end video cards do motion blur I think.) Moving images with no motion blur look very strange and sometimes confusing, and appear to flicker. (An example of this is the opening battle from Gladiator, in which motion blur was reduced to enhance the impression of chaos.) One way to simulate motion blur is to have tons of frames per second. For instance, if you have 5 times more FPS than your eye can perceive, then each five frames will effectively blur together, creating a more natural-looking motion with less flicker.
I'm sure there are more effects I haven't thought of, but you get the idea: it's not just about having enough frames to fool the eye. For #1, the key is not only high frame rate, but a frame rate sufficiently different from that of your ambient lighting (and its harmonics, I guess). For #2, the higher the frame rate the better: there is no limit. Fast-moving animations will always benefit from more FPS.
Read his book. Or, at least flip to the "turtles" part (I think it's near the beginning) and read that page.
The "turtles all the way down" reference is from a Brief History of Time by Stephen Hawking. You should read it. I was referring to any theory which simply begs the question. For instance, how did life evolve? Some answer that life didn't evolve on Earth, but rather came here from another planet. That simply begs the question, since it assumes that life already existed.
So, if you want to stick your head in the sand, you can say the universe began when the previous one ended. But doesn't that leave us with the question of how this infinite sequence of expanding and contracting universes came to be?
Thus, to me, the question of whether the universe is alternately expanding and contracting is mildly interesting, but not all that fundamental.
Bah. This is just another form of the "turtles all the way down" view of the world. If it's true, it just raises the question of how/when/why the whole lot started pulsating in the first place.
They just have to drop the "Ogg"--I think "Vorbis" is a great name.
Plus, it seems to me that 4M is too big for a lot of work. Having to page out entire 4M chunks every time paging occurs would kill performance. With today's hard drives, the delay to write 4M to disk is still observable by humans.
I have no experience with 4M pages, but it seems to me that they are not a general solution.
I don't follow. What's your point?
Who are you?? COWARD!
One thing that worries me about x86-64 is the page tables. They're 4 levels deep, and that still only gives a 48-bit address space. They stick with 4k pages. I guess they had to do it for backward compatibility, but to me this is clearly not the best approach.
Though, IA-64 is pretty questionable too. The VLIW aspect is cool, but the compilers are a nightmare. Nobody knows how to write compilers to take advantage of speculative execution, for one thing.
I'm not familiar with any other 64-bit architectures, but surely they're better than both of these?
I think the current state of affairs is that Jupiter is a planet because it does not do any fusion, and Pluto is a planet because everyone likes it too much to cast it back into the Cuiper belt.
But I have to say that when I first heard that a Cuiper belt object had a moon, my first thought was "hey, that's the second one after Pluto".
It's ok, those are fake names anyway. I mean, come on: Blasius Floch?
Wow, who modded this "Informative"?? :-)
You object to the "with it"? Seems ok to me. Removing it changes the meaning of the phrase.
..."
Personally I would totally rewrite this phrase, but I wanted to make minimize the change. That aside, my favourite is the one someone already posted: "Creative includes some closed-source software that allows them to sneak in per-call charges,