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Flash Drives Go To Work
feminazi writes "USB drive capacity is outpacing Moore's Law by doubling every year, evolving from tchotchkes to devices capable of addressing corporate needs ranging from mobile computing platforms to files stores with encryption and biometrics protection. SanDisk and M-Systems Flash Disk Pioneers launched a thumb drive with an intelligent U3 chip that can store and launch applications. Lexar's premium JumpDrive Lightning thumb drive has the fastest data-transfer rates at 18MB/sec write and 24MB/sec read. And some are strong on the outside, too. SanDisk touts a drive built to withstand 2,000 lbs. of pressure. Computerworld tested that claim by repeatedly driving a Volkswagen Beetle over the ruggedized thumb drive. While the drive's body came away with a few scratches, there were no dents, and not a single lost file."
Running the drive over with a car is at most going to be only 20-40 psi(pounds per square inche), the tire pressure. Maybe if the whole car was balanced on one wheel and then drove over it.
It's an old joke. Not even a joke. More sort of a thing that some computer programmers say sometimes and nod wisely to make their point.
It's a joke based on an old measure of bandwidth- from back in the day when modems were so slow that the fastest way to transfer a megabyte from LA to San Francisco was to load a station wagon with tapes and drive there.
Given a rough guess of 30,000 thumb drives, at 4GB per, on an 8 hour drive, you get 4GB/sec, give or take a GB, as the bandwith of a Beetle full of thumb drives.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
2,000 lbs. of pressure
2,000 lbs is not a pressure; there's no area. It's weight. This is basic high school physics...
Computerworld tested that claim by repeatedly driving a Volkswagen Beetle over the ruggedized thumb drive. While the drive's body came away with a few scratches, there were no dents, and not a single lost file."
A Neu VW beetle weighs about 3000lb. If the entire force applied against the road by one tire was applied to the device (for example, by putting a piece of thick metal on either side of the device and then running the car over the plate of metal), that's only 750LB. This is basic grade school math (3000/4.)
I'd guess your average thumb drive has perhaps 1-2 square inches of surface area. The amount of pressure between tire and road is exactly equal to the inflation pressure of the tire, which is often around 30-35 PSI (Pounds Per Square Inch.) So the thumb drive never had more than 60-70lb put on it...
Please help metamoderate.
This is from the 512MB model /dev/sdb1:
Timing cached reads: 2324 MB in 2.00 seconds = 1161.93 MB/sec
Timing buffered disk reads: 76 MB in 3.01 seconds = 25.26 MB/sec
Fast little thing
Ask for other benchmarks and I will run them.
Once again it's the attack of bad science! Not to mention a lack of regard for units.... Assuming all four wheels carry the same load (bad assumption) and the point of application of the load on the tire is constrained to a point (another horrible assumption), the pressure on the top face of the micro drive would be .25 * W_car (lbs) / A_disk (in^2). Note that this completely ignores St. Venant's principle, which is a nifty thing that explains how shear and normal stress is distributed along any given member. In reality, the stress wouldn't be uniform throughout the disk and would likely puncture the top of the drive before damaging the middle section.
Forgive me for the pedantry, but being a mechanical engineering student, I'm always irritated when people talk about pounds of pressure or use a kilogram as a measurement of weight. Argh!
Did you know subscribers can see articles in the future? Holy shit!
U3, huh. Why, when we have got Open Source goodness recompiled to run on flashdrives. ProtableApps.com. Fresh baked ClamWinAV Firefox OpenOffice Gimp Gaim and more.
Bless PortableApps.com
If a unicycle tire is at 50 psi with 100 lbs on it then there has to be 2 square inches touching the road, assuming the tire is flexible. A rigid tire could have less area in contact, but tires are flexible.
If you still don't understand, try googling or take a look at how to weigh a car by measuring surface area here
Oh, and a 100 lb woman in stiletto heels can exert over 1000 psi if she balances on her heel. We're talking about weight per unit area. Even though it is counterintuitive, you will exert more force per unit area on your bike than a bigrig full of i-beams, assuming you have higher pressure tires.
Man, you really need that seminar!
Here is Anandtech's last year USB Flash Drive Roundup: http://www.anandtech.com/showdoc.aspx?i=2549&p=3
It seems to be still relevant almost a year later. No faster models have come out from any of the major brands that I am aware of.
I must agree. After mistakenly buying a flash drive with a U3 chip, I've sworn never to go back. I've had very similar issues using these drives in work computers. Another issue: at least on the flash drive I bought, the 1 GB is the sum of the writable part of the drive AND the practically unusable U3 partition! ARG...
BB had the 1 gig's on sale so I bought a few to add to my toolbox. I found reformatting didn't get rid of U3, then went to the sandisk website and downloaded the uninstaller. Must be hidden somewhere on the drive, but at least the uninstaller trashed U3 for good :)
We have a research group here that does JPEG 2000 compression research. As you might guess, this generates staggering amounts of data. They don't transfer it over the network to other places, they FedEx harddrives. Turn out, with the amount of bandwidth the campus has and the slice they can easily get, 1TB is about the crossover point where FedEx overnight becomes faster. They usually FedEx a box with like 2-4TB worth of external harddrives in it, and get a similar box in return.
Sounds kinda silly, but really works out better overall. It's cheaper too, than it would cost to get the university to buy more bandwidth and dedicate it specially to them.
http://www.u3.com/uninstall/
One thing this is annoying about that--they recognize that Mac and Linux users might want to get rid of U3 (their survey that asks why you are getting rid of it includes using Mac or Linux among the answers), but the software to remove U3 only runs on Windows.
It did not work under Parallels on my Mac. I had to really boot Windows to run the U3 remover.
STAY AWAY FROM THIS DRIVE IF YOU ARE GOING TO KEEP ANYTHING REMOTELY IMPORTANT.
We purchased 3 of them for our IT staff in the local office. All 3 failed within 3 months of ordering, and 2 of the replacements failed after that (within a month of replacement). We had them switched out for some Cruzer Micro and Minis, and have been fine ever since (several months now).
My theory is the metal on the case. While strong, I think the metal in the case conducts static and shorts into the flash chips or USB controller inside. I don't even know if titanium conducts or not, and Sandisk denies there is a widespread issue with these drives, but go read the amazon.com forums on this product and you will be scared off.
It's a shame. They are a wonderful design, no caps to loose and the drive slides inside the case to protect the USB connector. But it's useless if you can't trust it. One of mine worked one second when I had it plugged into a laptop, then I dismounted it, walked 10 ft to my computer, plugged it in and it was DOA. I think it may have been the static from the carpet, I had it hanging around my neck. You're better off with a plastic one and just back it up periodically to protect against loss or damage.
-- Having a Creationist Museum is like having an Atheist place of worship
Most of the "engineers" reading here are not the "engineers" you (or I) consider to be real engineers. People typing at a keyboard and causing a display to show something are not engineers. 'Architect' might be a better description.
We've seen this too, but only with specific chip sets, and only ever on the "extra" USB ports. The ones on the back that are directly attached to the motherboard have all been fine, however the ones on top and front of case have the problems. I believe it is some sort of grounding problem. As such we have blanked out / disconnected those other ports and have yet to have any fail.
Ouch
My wife backed our Jetta onto my foot once, and then stopped it there when I yelled at her. (She claims it was accidental :) It wasn't comfortable, but it didn't break my foot either.
There's a large difference in teh weight on the front tires vs the weight on the rear tires of a front engine/front wheel drive vehicle. Assuming you care, you could find an old car magazine or road test, and itt'll list the weight balance, as well as the weight of the car. Being run over by the back wheels of a 80's econo-box (not saying that's what the Jetta is) is nothing.
On th eother hand, I have a heavy duty truck with tools, equipment, a utility bed and a Diesel engine. On DOT certified scales, theh front end (front wheels on the scale) weighs 4300 pound, while th erear wheels only put 3200 on the ground. Yup, each front tire is putting a ton onto the ground. That would hurt your foot.