Sure, if you only need 256MB of memory, the faster memory is better.
Memory's not something where you can trade speed for capacity. I don't care how fast it is, if you need more than 256MB you're going to be hitting swap every time you want to scratch your balls to remember where you put them.
More people are working on it, though. There was a bunch of buzz at an international lattice QCD conference this summer about porting lattice code to Cell -- the general consensus was that we're going to have to retune everything for a compute-rich, bandwidth-poor environment, but once all that's done and the code is ported over, Cell > x86 for performance per dollar.
This is from people who've actually tested stuff -- gotten a bunch of Cells and ported code and looked at numbers. I don't remember all the details but the folks doing it knew what they were doing.
It turns out single precision is enough for lattice QCD. The step that requires the most CPU time doesn't need to generate an exact result; it only needs to get close. If the result is too far off then you wind up wasting time, but the result will still be valid.
(This is the Metropolis procedure, if you're familiar with it: the accept/reject step takes care of any computational errors that occur)
You can -- that's what people are trying now. The issue is that in order for the GPU's to communicate, they've got to go over the PCI Express bus to the motherboard, and then via whatever interconnect you use from one motherboard to another.
I don't know all the details, but the people who have studied this say that PCI Express (or, more specifically, the PCI Express to Infiniband connection) is a serious bottleneck.
That product was actually specifically mentioned in the plenary talk at the 2009 Lattice Gauge Theory conference as the most likely contender for doing QCD on GPU's. It's still got the problem I mentioned, though -- not enough RAM to store everything, and not enough bandwidth to talk to the other units that are storing it.
Anyone doing forensics like this -- if they actually cared and weren't just being annoying Barney Fife types, which is sadly probably the case in the US -- wouldn't actually execute any code on a confiscated disk. Just looking at the bits that make up a virus isn't going to do anything nefarious -- you have to run them.
I do high-performance lattice QCD calculations as a grad student. At the moment I'm running code on 2048 Opteron cores, which is about typical for us -- I think the big jobs use 4096 sometimes. We soak up a *lot* of CPU time on some large machines -- hundreds of millions of core-hours -- so making this stuff run faster is something People Care About.
This sort of problem is very well suited to being put on GPU's, since the simulations are done on a four-dimensional lattice (say 40x40x40x96 -- for technical reasons the time direction is elongated) and since "do this to the whole lattice" is something that can be parallelized easily. The trouble is that the GPU's don't have enough RAM to fit everything into memory (which is understandable, they're huge) and communications between multiple GPU's are slow (since we have to go GPU -> PCI Express -> Infiniband).
If Nvidia were to make GPU's with extra RAM (could you stuff 16GB on a card?) or a way to connect them to each other by some faster method, they'd make a lot of scientists happy.
Ah. I've never used microSD for anything, so I have no idea how much you can store on it. My mom's camera takes SD and mine takes CF, so I'm familiar with those formats.
What if it's legitimately broken? I was carrying one of those through airport security once -- what happens if they say "Boot it" and you say "can't, the PSU is fried"?
Even if there *were* something nefarious someone could do with a few million bits on a computer, this sort of thing won't stop them.
If I want to get into the US with the Blueprints for the Big Terrorist Plot, all I have to do is encrypt them and upload them somewhere (terrorists can use gmail too!), come into the US with a machine with nothing on it, then get inside and download it again.
Flash memory cards have gotten big enough that you can store practically anything you want on one of them. What's to stop someone from buying a 32GB Compact Flash card, putting a couple of random cat pictures on it along with 31.9GB of Evil Terrorist Plot Data encrypted in a hidden filesystem, shoving it in a camera, and waltzing merrily through the checkpoint? Somehow I doubt they are willing to low-level-format every CF card that comes through the door. And, even if they do that, you can always just put it on a SD card and shove it up your butt.
Seriously, do they really think that they're going to be able to stop people from importing Evil Bits into the US?
Apparently Napolitano has lost her mind if she's allowing shit like this. She was the sole bit of sanity in the mad world that is Arizona state government until she left.
No, I didn't get that information from Michael Moore -- that's part of the historical record. Obvious troll is obvious. Let me guess -- you're not an American. Israeli?
And they're dinky compared to other AA missiles. $40,000 is "dinky" in modern warfare.
Shoulder-launched AA missiles are pretty cheap -- we're not talking about the serious SAM's used to shoot down jets, but the dinky little things that we gave Bin Laden to shoot down Soviet helicopters.
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Cell, in theory, if you can figure out how to use all those cores on a computer that's crippled otherwise.
Sure, if you only need 256MB of memory, the faster memory is better.
Memory's not something where you can trade speed for capacity. I don't care how fast it is, if you need more than 256MB you're going to be hitting swap every time you want to scratch your balls to remember where you put them.
256MB isn't enough for modern desktop computing.
More people are working on it, though. There was a bunch of buzz at an international lattice QCD conference this summer about porting lattice code to Cell -- the general consensus was that we're going to have to retune everything for a compute-rich, bandwidth-poor environment, but once all that's done and the code is ported over, Cell > x86 for performance per dollar.
This is from people who've actually tested stuff -- gotten a bunch of Cells and ported code and looked at numbers. I don't remember all the details but the folks doing it knew what they were doing.
That too.
It turns out single precision is enough for lattice QCD. The step that requires the most CPU time doesn't need to generate an exact result; it only needs to get close. If the result is too far off then you wind up wasting time, but the result will still be valid.
(This is the Metropolis procedure, if you're familiar with it: the accept/reject step takes care of any computational errors that occur)
You can -- that's what people are trying now. The issue is that in order for the GPU's to communicate, they've got to go over the PCI Express bus to the motherboard, and then via whatever interconnect you use from one motherboard to another.
I don't know all the details, but the people who have studied this say that PCI Express (or, more specifically, the PCI Express to Infiniband connection) is a serious bottleneck.
That product was actually specifically mentioned in the plenary talk at the 2009 Lattice Gauge Theory conference as the most likely contender for doing QCD on GPU's. It's still got the problem I mentioned, though -- not enough RAM to store everything, and not enough bandwidth to talk to the other units that are storing it.
Anyone doing forensics like this -- if they actually cared and weren't just being annoying Barney Fife types, which is sadly probably the case in the US -- wouldn't actually execute any code on a confiscated disk. Just looking at the bits that make up a virus isn't going to do anything nefarious -- you have to run them.
And people doing industrial espionage carry their secrets on hard drives mounted in laptops across the border, unencrypted?
That makes me wonder what the difference between analog and digital really is. Is a barcode considered analog or digital? What about a page of text?
Clearly both are analog representations of fundamentally digital data, but I doubt lawyers are bright enough to address this :P
I do high-performance lattice QCD calculations as a grad student. At the moment I'm running code on 2048 Opteron cores, which is about typical for us -- I think the big jobs use 4096 sometimes. We soak up a *lot* of CPU time on some large machines -- hundreds of millions of core-hours -- so making this stuff run faster is something People Care About.
This sort of problem is very well suited to being put on GPU's, since the simulations are done on a four-dimensional lattice (say 40x40x40x96 -- for technical reasons the time direction is elongated) and since "do this to the whole lattice" is something that can be parallelized easily. The trouble is that the GPU's don't have enough RAM to fit everything into memory (which is understandable, they're huge) and communications between multiple GPU's are slow (since we have to go GPU -> PCI Express -> Infiniband).
If Nvidia were to make GPU's with extra RAM (could you stuff 16GB on a card?) or a way to connect them to each other by some faster method, they'd make a lot of scientists happy.
Ah. I've never used microSD for anything, so I have no idea how much you can store on it. My mom's camera takes SD and mine takes CF, so I'm familiar with those formats.
They've already ruled that copying is stealing. Funny how that only applies to us...
What if it's legitimately broken? I was carrying one of those through airport security once -- what happens if they say "Boot it" and you say "can't, the PSU is fried"?
Even if there *were* something nefarious someone could do with a few million bits on a computer, this sort of thing won't stop them.
If I want to get into the US with the Blueprints for the Big Terrorist Plot, all I have to do is encrypt them and upload them somewhere (terrorists can use gmail too!), come into the US with a machine with nothing on it, then get inside and download it again.
Flash memory cards have gotten big enough that you can store practically anything you want on one of them. What's to stop someone from buying a 32GB Compact Flash card, putting a couple of random cat pictures on it along with 31.9GB of Evil Terrorist Plot Data encrypted in a hidden filesystem, shoving it in a camera, and waltzing merrily through the checkpoint? Somehow I doubt they are willing to low-level-format every CF card that comes through the door. And, even if they do that, you can always just put it on a SD card and shove it up your butt.
Seriously, do they really think that they're going to be able to stop people from importing Evil Bits into the US?
Apparently Napolitano has lost her mind if she's allowing shit like this. She was the sole bit of sanity in the mad world that is Arizona state government until she left.
Nobody'd ever have gone to the moon in the first place if it weren't for a Kennedy, fyi.
I taped some pennies to her paper with a note: "This *arrow* is currency."
I was admonished by my boss not for being snarky but because money changed hands. :P
"The batter pushes currency through the wire." ... even with spellcheck my students manage to sound like dipshits (college EM lab)
Religion and xenophobia, often combined.
I think criticizing Venezuela for hypocrisy, as the summary did, is just fine.
Just because the same criticism is also valid for the US doesn't make it any less valid elsewhere.
Does this mean that this collectivism should be enforced by law?
European culture is more collectivist too, but the Europeans realize that this cultural trait doesn't need to be enshrined in law.
No, I didn't get that information from Michael Moore -- that's part of the historical record. Obvious troll is obvious. Let me guess -- you're not an American. Israeli?
And they're dinky compared to other AA missiles. $40,000 is "dinky" in modern warfare.
Hydrogen is actually a larger molecule than helium, since it's diatomic.
The thing is huge and doesn't move, making the guidance task of whatever you shoot at it very easy.
Shoulder-launched AA missiles are pretty cheap -- we're not talking about the serious SAM's used to shoot down jets, but the dinky little things that we gave Bin Laden to shoot down Soviet helicopters.