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Computer hardware revolution!who know more about solid state disk ?

  1. Oct 17, 2008 #1
    In future HDD will be replaced by solid state disk,SSD will become the mainstream.
    Solid State Disk (SSD): it is a general definition to distinguish traditional mechanical drives which depends on complex mechanical parts and control circuits, bascially any drive with electronics storage media can be called as SSD, but in current mainstream market, the SSD was defined as " a drive with NAND flash in standard form factors (1.8,".
  2. jcsd
  3. Nov 6, 2008 #2
    I think you are right, but what is your point?
  4. Nov 6, 2008 #3
    It seems that you know SSD better .If possible please send me a PM
    I want to consult you something about SSD.
    Last edited by a moderator: Nov 20, 2008
  5. Nov 12, 2008 #4
    Post your query on here so we can all have a go at answering it for you.

    You have nothing to lose and you will only widen your response.
  6. Nov 12, 2008 #5
    Nobody knows if SSD will replace HDD. Up to now, SSD are small and expensive, and HDD make progress as well - perhaps faster than SSD.

    One may hope to combine both in order to accelerate chosen software. More likely in the near future.

    However, I shall like to underline that many SSD are desperately SLOW. They may compete against a fair 2.5" HDD, but are much slower than a honest 3.5" HDD.

    One good explanation is that HDD are much faster when serving many requests for files located close to another - which is the case with Windows beginning with Win98. Even better, beginning with XP, all files an application needs are requested from the disk before the application actually notices it will need them (browse "prefetch").

    Then, "random access time" is really uninteresting as a performance measurement. Programs like AttoDisk give figures that reflect far better the user's experience, and this tells that good HDD are much better than almost any SSD now available.

    The same holds for CF (Compact Flash) cards, which have generally better figures than SSD, but start Win and the applications less quickly than a good HDD does.

    The situation is quite different for notebooks, where all HDD are very bad. Don't buy notebooks, this is just one excellent reason. There, a SSD is an improvement. Or rather a CF card, better and much cheaper.

    However, I wish I could try the last SSD toys by Intel. These ones look great.
    Last edited: Nov 12, 2008
  7. Nov 19, 2008 #6
    What algorithm does AttoDisk use to test performance? Isn't the random access time what makes SSD so desirable in the first-place? Hardware does affect the performance of file access, but so does the OS, file-system's implementation, and how it's actually used also affect performance along with hardware.

    Additionally, the weight of the factors I mentioned vary depending on the situation. For instance, using a filesystem which makes use of random access wouldn't provide good results for when storage is usually accessed in a sequential order - regardless of hard ware.
    But, what gives an SSD the theoretical performance edge, is that it's made of the same stuff as fast, volatile storage devices, which is that it's made of semiconductors. Whereas, an HDD is composed of an arm which flies over a magnetic disk. In spite of how the file-system is implemented, it's biggest flaw is that you still have to consider the time it takes for the arm to physically move from one point to another. However, this isn't the case with SSD.

    When you don't consider how the filesystem is used or how it's written, it seems that SSD should outperform an HDD (as it does) since the SSD isn't bounded by the time it takes for its moving parts to move - as it doesn't have any.
  8. Nov 20, 2008 #7
    I think you should work more with light, laser or anything else. For what is the use to start on making a bigger memory hdd if you can start using light instead. if a screen can start with on light base. meaning, there are millions of color of light, if you make a screen, any screen based on natural light, not by led, oled, or tft, than there are unnumbers of possibilities, with clearity of 0,000009 of pixel. and with crystals you can do even more.
    If you do the same with a hdd but instead of magnetical way, the light way, higher form of magnetical way, the space you create and can get back goes at speed of light, meaning, 3 to 100GB per second or even more faster to get your information you stored. if you use than fiber optic, optical way, even super computer will be still slow.

    I am creating now a screen based on light with the pixel thickness of 0,000009 , the screen itself is 3 mm(europe standard), with combination with such a memory storage, everything will be blown away.

    I am a visual spatial learner, and I see those tools, things just in my mind how to work, how to let it work, and etc.
  9. Nov 20, 2008 #8


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    SSD has different properties than HDD, some good some bad.

    Very fast sequential read
    Very fast random read
    No rewrite capability, must erase before a write.
    Erase is very slow and is done on a large block (128 KB - 256 KB )
    Write is very slow and is done on a page level (64 pages in a block - 4 KB).
    Fast sequential write.
    But random write is very slow.
    All NAND has a finite number of program/erase cycles (so data must be moved around to average wear)

    There are new filesystems being developed especially for flash that gets around this by using a more database centred approach to batch writes together and use agarbage collection system to erase old data duringidel times.
  10. Nov 21, 2008 #9
    How does a one store light? I can see how fiberoptics work with communication, but is a data-storage system based on light feasible? If so, is it practical on a home/office desktop or workstation environment?
    A magnetic disk is pretty reliable and you can store information on it by way of a magnetic charge. However, a light source has to be continuously be produced in order for you to maintain it. Light in itself, isn't something you can store by charging anything.

    Instead, you can only store light on things which react to it chemically (ie photograph), or in the form of some other kind of energy such as in heat or electricity. In either case, you wouldn't be able to store information on it so easily because most things which react to light are permanently affected by it.

    This is why HDD use magnets instead of laser-disks, because magnets are still more reliable.
  11. Nov 21, 2008 #10
    Yeah, like a transaction kind of system? I remember reading something about databases and transactions in my OS text-book. I think using a journaling system can help out a whole lot, when information has the potential to be lost. I forget how they implement on hardware, however.

    I wouldn't see how a transaction journal would be stored on a temporary memory system without the use of batteries or some back-up source of energy. But, I'm guessing that in the case of SSD's, treating it in the way you do databases works in that you can make all the changes at once, storing the transaction journal on main memory until later, instead of modifying the disk as you go like you do with HDD's.
  12. Dec 8, 2008 #11
    how to store with light, light has got many color but you can change the color of light, so if you than make 1 light into 2, you have a beam of light, and this can be nanometer thick. So you can store light very far away from your own screen. I couldn't write earlier, I was ill for a week and a half.
  13. Dec 9, 2008 #12
    But, can I turn my computer off and still have my data on storage using light instead of magnetic disks or SSD?
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