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Terabyte Hard Drive Put To the Test
EconolineCrush writes "As a technical milestone, Hitachi's Deskstar 7K1000 hard drive is undeniably impressive. The drive is the first to pack a trillion bytes into a standard 3.5" form factor, and while some may argue the merits of tebi versus tera, that's still an astounding accomplishment. Hitachi also outfitted the drive with 32MB of cache—double what you get with standard desktop drives—making this latest Deskstar a leader in both cache size and total capacity. That looks like a great formula for success on paper, but how does it pan out in the real world? The Tech Report has tested the 7K1000's performance, noise levels, and power consumption against 18 other drives to find out, with surprising results."
Conclusion in the article: Too expensive.
In my experience, when S.M.A.R.T. tells you a drive is dead or dying, its not kidding.
That's nonsense. It isn't even true in theory. (at some point the remaining charge is below the noise-floor) If it wasn't you could store an infinite amount of data on a drive by simply filling it once with dataset1, overwrite by dataset2, overwrite by dataset3 and so on. You claim dataset1 will always be recoverable, so in this method, you could recover each of the sets and have stored triple amounts of data on the drive. You claim *any* amount of overwriting will be insufficient, so I guess I can store 1000 datasets on the drive then. Cool. Hint: The real world doesn't work like that
/dev/hda | strings" will recover huge amounts of text from a hard-drive which has been erased in this manner.
Secondly, even if in theory you where rigth (which you aren't), in *practice* most data is not valuable enough that theres much real risk that anyone will recover it, even after something as simple as a one-time-all-nulls overwrite. (which is just about the suckiest overwrite you can do) Yes, in that case an expert lab *can* recover it, but odds are it won't happen.
In practice, if you do the standard wipe, which is usually some variant of all-nulls, all ones, 3 times random, there is -zip- chance that anyone will be able to get at the data that was once on the platter.
Now, what many (clueless people) do are "format" the drive or "delete" the files. These functions don't overwrite even once 99% of the platter, so files removed in this manner are certainly recoverable -- they're there in plaintext, just not referenced from the filesystem anymore. Something as simple as "cat
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A 128 kbit/s audio stream is 128 * 10^3 bit/s (power of 10)
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A 100 Mbit/s ethernet card is 100 * 10^6 bit/s (power of 10)
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A 480 Mbit/s USB2 link is 480 * 10^6 bit/s (power of 10)
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A 500 GByte disk is 500 * 10^9 bytes (power of 10)
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A 56 kbaud modem is 56 * 10^3 baud/s (power of 10)
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A 1.5 GHz processor is 1.5 * 10^9 Hz (power of 10)
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A 6 Mbit/s DSL line is 6 * 10^6 bit/s (power of 10)
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A 650 MByte CD is 650 * 10^6 bytes (power of 10)
It is a total mystery to me why people think that power-of-2 prefixes should be the norm, when the only few places where they are used are to refer to the size of files and RAM sticks.Spread the truth. Mod me informative
I've RTFA, and still don't get what the 'surprising results' is supposed to be.
It has huge capacity - check.
It is noisy and sucks power - check.
It is not a speed champion - check.
Not exactly surprising for the first 1TB drive on the market.
If J.K.R wrote Windows: Puteulanus fenestra mortalis!
Because it isn't safer, at least not unless you have a battery-backed interface card *anyway*. And usually the only cards with battery-backing are... hardware raid cards. I have been known to use linux-md on an old hardware raid card, when the card had a very slow processor. But these days, raid cards have processors in the 300-600 MHz range, AND ASIC or FPGAs to do parity. They're more than adequate.
Also, linux-md doesn't guarantee ordering, which hardware-raid cards, as they're intended for use with oracle and friends, do.
Yesterday at a Best Buy in Ohio a guy and his wife were looking at 42" Sony LCDs. There was a 1080P for $1899 and a 1080i for $1599. Guy asked the sales associate what the difference was.
Sales associate, I shit you not, said "The "P" is actually a newer product. It is 7 minor revisions later. We still carry the "i" because it's still very popular. The same thing happens with our wireless equipment, too. the "N" version is out, but most users are still buying the "G" Version"
I approached the guy after the sales associate left and said "listen, that guy has no clue what he's talking about. I is interlaced, P is progressive. On an "i" it's drawing 540 lines every frame, on a "p" it's drawing all 1080. Go with the "P" if you can afford the difference. It's worth it"
I lost 3 drives out of 6 within a few hours of each other. Raid 1+0 saved my bacon. Zero down time. Got the email alert about the first drive, and scheduled a trip to the datacenter. Then I got the other two back to back a couple hours later. These were all 15K rpm SCSI drives which had survived a 2 week stress test burn-in, and had been in production for about a year, so it was totally unexpected. In another case, I lost 2 drives in a Raid 5 and had to resort to restoring the machine from backups - a day lost. Raid 6 performance is even worse than Raid 5, so I personally see no point - YMMV. Raid 5 and 6 rebuild time is also VERY slow compared to 1+0, taking 3 times longer in my testing.
Anyway, what's that old saying? Expect the unexpected? When you buy a pile of drives, you are likely to get the batch from the same manufacturing line, day, etc. This probably also increases the chances of simultaneous failures if there is a physical quality problem. If you have two fail, expect a third. I generally don't mix up batches because I want to know where all the drives from a particular batch are, but maybe I should.
Maybe 1023 tons of TNT is what fits on a standard truck, so it would be handier than that stupid 1000 for a kiloton.
Are those "long" tons (2240lb), "short" tons (2000lb), or "metric" tons (1000kg)?
Ambiguous terms of measurement do exist outside of the computer industry, too -- which, I should point out, is actually "the software development industry" plus "the hardware manufacturing industry" plus "the IT service industry" and so forth.
Drive manufacturers have always used base-10 prefixes to describe the capacity of winchester drives. It's not a marketing ploy, it's historic convention.