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WD's Monster 2TB Caviar Green Drive, Preview Test

Posted by timothy on from the what-would-this've-cost-in-1999? dept.

MojoKid writes "Today Western Digital is announcing their WD20WEADS drive, otherwise known as the WD Caviar Green 2.0TB. With 32MB of onboard cache and special power management algorithms that balance spindle speed and transfer rates, the WD Caviar Green 2TB not only breaks the 2 terabyte barrier but also offers an extremely low-power profile in its standard 3.5" SATA footprint. Early testing shows it keeps pace with similar capacity drives from Seagate and Samsung."

39 of 454 comments (clear)

  1. Powers of 2 by Hyppy · · Score: 3, Informative

    It's really only 1800 Gigs.

    1. Re:Powers of 2 by wild_quinine · · Score: 5, Funny

      It's really only 1800 Gigs.

      Ah, the drivemaker's kilobyte...

    2. Re:Powers of 2 by corsec67 · · Score: 3, Informative

      You mean 1800 Gibibytes?

      --
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    3. Re:Powers of 2 by pushing-robot · · Score: 5, Funny

      Yes. Curse those evil companies, trying to replace our God-given units—like Furlongs, Hogsheads, and Binary Thousands—with evil, communist SI units. The fiends will stop at nothing to pollute the American way of life!

      --
      How can I believe you when you tell me what I don't want to hear?
    4. Re:Powers of 2 by jedidiah · · Score: 4, Interesting

      Yeah... nevermind units that fit in with what's being measured
      or are computationally convenient. What we really need are
      arbitrary metrics created by beaurocrats on a power trip.

      --
      A Pirate and a Puritan look the same on a balance sheet.
    5. Re:Powers of 2 by fprintf · · Score: 3, Funny

      The funny thing is both of my home computers have drives smaller than the missing 200GB from this 2TB drive. I really need to upgrade soon...

      --
      This post brought to you by your friendly neighborhood MBA.
    6. Re:Powers of 2 by MightyYar · · Score: 4, Insightful

      Your argument would carry more weight if the manufacturers were doing this for the benefit of humans. In fact, they mix units - using the 1024-standard units for cache. Tell me mixing units is friendly! :)

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    7. Re:Powers of 2 by sexconker · · Score: 4, Insightful

      Let me explain this is detailed, complicated-for-you, terms.

      Exponents are useful for counting possible combinations. Computers are logically binary and quantum. When dealing with storage, we use 1024, because it represents the number of possible configurations of a 10-bit sequence.

      2^10 was chosen for convenience - it was close to 1000, which people are used to working with, and it provided a good separation between major units.

      1000 was chosen by SI for reasons just as arbitrary, namely providing a good spacing. We have scalar units of 10 (decimeter, decameter, for example), but no one ever says "Go down the road 1.2 deca kilometers".

      SI units (major units based on a factor 1000, with shitty units based on 10 for completeness) are for measuring.

      Computery units, (major based on a factor of 1024, with minor units based on 2 as the basis), are for counting.

      This is why clock speeds use 1000, not 1024. Clock speeds are traditionally measured, and not counted, and they do not operate on a binary quantum system.

      This is why data storage is SUPPOSED to be described using 1024, while data transfer is described using 1000.

      If you want to get down to it, all SI units are retarded, since the universe is quantum (it is). All measurements are merely inaccurate tools of convenience, and everything should be counted in universal quantums of space (Planck Length? I doubt it, unless it really is tortoises all the way down), time, etc.

      To sum it up - SI is not right because it's "official". SI is WRONG for computer science. And if the universe is quantum, SI is technically wrong for everything. Calculus, too.

    8. Re:Powers of 2 by mmontour · · Score: 4, Interesting

      Your argument would carry more weight if the manufacturers were doing this for the benefit of humans. In fact, they mix units - using the 1024-standard units for cache.

      RAM specifications use the 2^x numbering because the device is physically constructed as a square grid of cells with power-of-two numbers of rows and columns. There's a direct mapping between bits on the address bus and the cell that is selected.

      In the early days it was convenient to say that 1024 was close enough to 1000, so RAM sizes were quoted in "KB". However, the error in this increases with each step up in size. By the time you get to the TB scale it's no longer a reasonable approximation.

      Magnetic storage does not have this constraint. The sector size is (arbitrarily) set at 512 bytes and hard drives usually have an even number of read/write heads, but apart from that there are no powers of two. The number of cylinders on the drive, and the number of sectors per cylinder, are arbitrary.

      Communication speeds (e.g. "9600 baud", "100 Mb/s") are also not specified in power-of-two sizes, because they are natively dealing with individual bits and not power-of-two-sized chunks.

      Therefore, there is nothing wrong with saying that a drive is "1 TB with 32 MiB of cache". As long as the manufacturer uses the SI and kilobinary notation correctly, users should not complain. Save your anger for the marketroids at WD who come up with features like "IntelliSpeed" in order to sell you a 5400-RPM drive and make you think you're buying a 7200-RPM one.

      tl;dr version: Just use the damn GiB/GB notation consistently and get over it.

    9. Re:Powers of 2 by Al+Dimond · · Score: 4, Insightful

      SI might be wrong for computer science, but SI prefixes have standard meanings. If we want prefixes that work better for computing (which we may well), then making new ones, just to be clear, is a good idea. Then if SI is wrong you don't have to use it, and you don't confuse everyone by using its terminology to mean something slightly different (which is much worse than using it to mean something very different).

      Anyway, the power-of-two units make some calculations easier and many harder. Just because an N-bit MUX has 2^N inputs doesn't mean they'll all be connected to something. You have 4 384-byte memory modules, quick, how many kB? Um, what's 384/1024? 3/8 maybe? Having to mess with mutliplying/dividing by 1024 in the middle of back-of-the-napkin calculations where not every number is a simple power of 2 (even if many of them have lots of 0s at the end in binary, like 384 does) actually does suck unless you just give in and learn your multiplication tables in hex (if I was still doing driver programming I probably would have done just that).

    10. Re:Powers of 2 by Just+Some+Guy · · Score: 5, Funny

      You mean 1800 Gibibytes?

      I will never, ever, in my entire life, even once mean "gibibytes".

      --
      Dewey, what part of this looks like authorities should be involved?
    11. Re:Powers of 2 by petermgreen · · Score: 3, Insightful

      Well binary units make sense for the size of solid state memories because they were almost always produced in power of two sizes (for good reasons, if they weren't the address decode logic would be a LOT more complex). Binary kilobytes also made sense for floppies since they were usually an integer number of power of two sized sectors.

      And if your OS is already using a measuring system for memory and floppies doesn't it make sense to also use it for hard drives? MS clearly thought so. Unfortunately the hard drive vendors throught differently (whether for technical reasons or because it allowed them to advertise higher capacities is unclear) and so we ended up with two different systems in wide use.

      Worse with each unit we go up the discrepancy gets worse. At kilo it was only 2.4% , at terra it's nearly 10%.

      --
      note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
    12. Re:Powers of 2 by mdielmann · · Score: 4, Insightful

      Um, yeah, except that just about everything is stored on powers of two. This is as absurd as if hot dogs were sold in packages of 8 (or 1024) and buns were sold in packages of 10 (or 1000). AND they used the same term to describe both, until it got to the point where they could sell significantly less than was expected while using VERY small print to notify us of this change in wording.
      There is absolutely NO reason to use base 10 numbering for computer memory of any kind, except that it allows manufacturers to use bigger numbers while selling less. The only mitigating factor is that now that they all do it, at least we're back to comparing apples to apples.

      --
      Sure I'm paranoid, but am I paranoid enough?
    13. Re:Powers of 2 by mmontour · · Score: 3, Insightful

      Now explain flash/solid state memory sizes and the "formatted capacity" of memory.

      At a low level flash chips have a row/column nature similar to DRAM, but there is additional complexity because some operations target a larger "erase block" rather than an individual byte.

      Some embedded platforms present a raw interface to the flash memory and require the host operating system to provide support for bad blocks and wear-levelling. These would be specified in "MiB" along with a certain allowable percentage of bad blocks.

      However, the more familiar approach (e.g. in a SD card) is to include an embedded microcontroller that presents a logical block interface to the host. This controller skips over the bad blocks, and also needs to use some of the good blocks to keep track of the logical-to-physical block mapping. Here it makes more sense to use SI notation.

      I just checked an "8 GB" microSD card and found that it presents a capacity of 7969177600 bytes to the OS (before partitioning). So 0.4% of the rated capacity is not available to me. This is consistent with the typical fine print on the package, e.g. "Some of the listed capacity is used for formatting and other functions, and thus is not available for data storage" (from Sandisk's website). If the manufacturer had sold it as an "8 GiB" card I would be more upset because that would represent a 7.3% capacity loss.

    14. Re:Powers of 2 by RzUpAnmsCwrds · · Score: 3, Insightful

      To sum it up - SI is not right because it's "official". SI is WRONG for computer science. And if the universe is quantum, SI is technically wrong for everything. Calculus, too.

      No one gives a shit whether your measurement system is 'correct', as long as it's consistent. SI is VERY consistent for a system that spans so many fields. That's why it's better than the US customary system.

      This is why data storage is SUPPOSED to be described using 1024, while data transfer is described using 1000.

      There's nothing inherent to today's storage technologies that requires power-of-two capacities. We're not even using a fraction of the address space we already have, so sticking to a power-of-two size doesn't have any real benefits.

      SI is WRONG for computer science.

      Oh, so Computer Science is so important that we get to invent our own units, and use the same names as established SI units? Please. If you want to use binary units because they are convenient, go ahead and do so. But DON'T call them "tera", "giga", or "mega"; these terms already have SPECIFIC meanings and you can't just hijack them.

  2. That was quick. by jcr · · Score: 4, Insightful

    Wasn't it only about a year ago that 1TB drives hit the market?

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
  3. just what I need by Coraon · · Score: 4, Funny

    I was worried I would have to start deleting from my *cough* adult movie collection *cough* to make more room

    --
    -Ours is the wisdom of Solomon, the magic of Merlyn, the fall of Icaris.
  4. backups by Reality+Master+201 · · Score: 4, Interesting

    What the hell do you do to back up your 2TB drive?

    That much storage in a single unit seems kind of dangerous.

    1. Re:backups by Moridineas · · Score: 5, Insightful

      What the hell do you do to back up your 2TB drive?

      2 other 2TB drives?

    2. Re:backups by timeOday · · Score: 5, Insightful

      That much storage in a single unit seems kind of dangerous.

      I never understood this argument. Say you have N drives each with capacity C/N (e.g. C=2TB, N=1 for this new drive, or C=500GB, N=4 as you prefer) and probability P of each drive failing in a given time interval. Your expected data loss is N*P*C/N, which is independent of N. So what's the gain from more drives?

      Heck, assume you don't want the hassle of multiple partitions so you use logical volume management to concatenate the drives (simulating the larger disk). Since any failure kills the whole thing, it's even worse - N*P*C.

      I guess maybe your are thinking of RAID5? But is this an enterprise-class hard drive? I'm not buying (or buying electricity for) 3x 1TB drives instead of 1x 2TB drive just to protect my PVR recordings. And since RAID (regardless of level) is not a backup, if the data is any more important than PVR recordings, you still need backups with or without RAID. So all RAID5 gives you is decreased time to recover from a broken drive, by making you buy a spare up front. Obviously decreased downtime is critical for an important server, but not for the vast majority of home PCs.

    3. Re:backups by corsec67 · · Score: 4, Insightful

      Except RAID isn't a backup, so your data isn't that "safe and happy".

      --
      If I have nothing to hide, don't search me
    4. Re:backups by binarylarry · · Score: 4, Funny

      hmm, nope.

      No one was confused. Nor would they care if they were.

      --
      Mod me down, my New Earth Global Warmingist friends!
    5. Re:backups by ColdWetDog · · Score: 3, Insightful

      Actually a multi terrabyte RAID 5 drive is a nice bit of the backup solution. No, it's not the be all and end all of backups. You still need separate completely off line and off site backups. But since modern RAID boxes can tell if a drive is bad, you get to look at the blinken light, go "oops", pull the drive and plug another one in. Wander off to Slashdot for a few hours and poof. Your data is back. No muss, no fuss. I like that part.

      You can never be too rich, too thin or have too many backups. At least I get the chance to do one out of three....

      --
      Faster! Faster! Faster would be better!
    6. Re:backups by bendodge · · Score: 5, Informative

      There's another problem. Take a look at this excellent article:
      http://blogs.zdnet.com/storage/?p=162

      SATA drives are commonly specified with an unrecoverable read error rate (URE) of 10^14. Which means that once every 100,000,000,000,000 bits, the disk will very politely tell you that, so sorry, but I really, truly can't read that sector back to you.

      ...

      Disk drive capacities double every 18-24 months. We have 1 TB drives now, and in 2009 we'll have 2 TB drives.

      With a 7 drive RAID 5 disk failure, you'll have 6 remaining 2 TB drives. As the RAID controller is busily reading through those 6 disks to reconstruct the data from the failed drive, it is almost certain it will see an URE. So the read fails. And when that happens, you are one unhappy camper. The message "we can't read this RAID volume" travels up the chain of command until an error message is presented on the screen. 12 TB of your carefully protected - you thought! - data is gone. Oh, you didn't back it up to tape? Bummer!

      --
      The government can't save you.
  5. Perfect by timeOday · · Score: 4, Insightful

    Spindle-drives are inherently slow anyways, so I think the combination of a big, power-efficient drive (never mind the speed) for movies and an SSD drive for everything else is ideal.

  6. Nice by Anonymous Coward · · Score: 5, Interesting

    The cache on this drive is 8x larger than the capacity of my first hard drive.

  7. WD20? by argent · · Score: 5, Funny

    It'll be so slick when the 4.0 TB WD40 comes out.

  8. backups-Blowups. by Ostracus · · Score: 3, Insightful

    Unless they're all the same model made in Thailand.

    --
    Shai Schticks:"You don't make peace with friends, you make peace with enemies"
  9. But how reliable is it? by jollyreaper · · Score: 4, Funny

    Agent smith: What good is 2 terabytes of porn if you are unable to access it?
    Keanu: (glances worriedly at his zipper)
    agent smith: (palm to face, shakes head) The hard drive, you imbecile, the hard drive.

    --
    Kwisatz Haderach
    Sell the spice to CHOAM
    This Mahdi took Shaddam's Throne
  10. Green Caviar? by auric_dude · · Score: 5, Funny

    No thanks, looks and smells a bit fishy to me.

  11. Fools say it's DANGEROUS! by TheMiddleRoad · · Score: 3, Insightful

    Every time a new, larger drive comes out, people say, "That much data in one drive is dangerous!"

    So here's what you do. Go buy ten 200GB drives. RAID them together. Who do you think will lose data, you, with ten times the possible failure points, or me with only one?

    Just back it up, biznatch!

  12. Re:That was quick, but normal by ChienAndalu · · Score: 3, Informative

    Apperently they are the same. I was a little bit surprised, too.

  13. More room... or backup? by TheMiddleRoad · · Score: 4, Insightful

    The problem with a larger drive is I fill it quickly. Should I buy a 2TB drive and use it to backup my already full two 1TB drives, or should I just add storage? Oh, the agony!

  14. I'll lose less data by Reality+Master+201 · · Score: 3, Insightful

    My RAID setup would use drives from different manufacturers and production lots, and contain hot spares.

  15. Re:That was quick, but normal by Anonymous Coward · · Score: 5, Interesting

    Hard drive capacity is no longer exponential. They have hit some limits that are pretty hard to overcome. They're still making progress but not nearly as fast as in years past. Additionally, drives larger than 640 GB or so seem to have some reliability problems. I just recently upgraded my RAID arrays and went with smaller 640 GB drives because they have proven more reliable even though it would have been cheaper for me to go with newer larger drives.

    The OP was wrong about it being one year anyway.

    I hate hard-drives. I wish SSD technology would improve. It's not just price, the current drives are unreliable as hell. I trust regular old mechanical spinning devices a lot more than the current SSD crap.

  16. 7 hours? by mikeee · · Score: 3, Interesting

    It's worse than you think. Even if you have a place to back it up, the I/O rates on modern HDs aren't increasing nearly as fast as capacity. Reading at top speed, it would take almost 7 hours to pull all the data off this drive, even if you have someplace to put it. Similarly, if you're using it as part of a RAID set, it'll take that long to rebuild if you have a failure.

    Pretty soon the MTBF on these drives will be a significant fraction of (capacity)/(read rate); that will make for fun all around.

  17. 32MB On Disk Cache by 3p1ph4ny · · Score: 3, Interesting

    I was thinking about this the other day, but, does the 32MB on disk cache really matter?

    Think of it this way: the Linux kernel does disk caching with my free RAM (which I generally have more than 32MB of) according to some reasonable locality scheme (LRU or something).

    If the HDD does the same caching according to nearly the same principles, won't the data on the disk cache nearly always be a subset of the disk cached in RAM? Meaning: doesn't the disk cache have no effect whatsoever?

    I'm genuinely interested in an answer to this question, even if it is a little OT. Please burn a little karma for me :)

    1. Re:32MB On Disk Cache by drsmithy · · Score: 4, Informative

      If the HDD does the same caching according to nearly the same principles, won't the data on the disk cache nearly always be a subset of the disk cached in RAM? Meaning: doesn't the disk cache have no effect whatsoever?

      No, because the OS does not know about the physical layout of sectors on the disk and the HDD controller does. Therefore, it can reorder requests appropriately to maximise performance.

      Disabling the cache on a hard disk gives a massive performance hit, especially for writes. They become nearly an order of magnitude slower.

  18. Re:What's the effing power consumption? by rthille · · Score: 3, Informative

    Well, you could click twice more, once on this (in the linked PR) http://wdc.com/en/products/Products.asp?DriveID=576 and then on the "Specifications" tab (I hate web 2.0 shit like this where you can't properly link to content).

    Power Dissipation
            Read/Write 7.4 Watts
            Idle 4.0 Watts
            Standby 0.97 Watts
            Sleep 0.97 Watts

    For comparison, here are the number for the 1TB (32MB cache)
    Current Requirements
            Power Dissipation
            Read/Write 5.4 Watts
            Idle 2.8 Watts
            Standby 0.40 Watts
            Sleep 0.40 Watts

    I don't understand why Standby/Sleep power use more than doubled... As for the Active, I assume that's due to spinning 2x the platters and added processing power to be able to process the data coming off those platters 2x the speed.

    --
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