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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."

6 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 corsec67 · · Score: 3, Informative

      You mean 1800 Gibibytes?

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

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

  3. 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.

  4. 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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  5. 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!

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