Incremental image and disk defragmentation

Discussion in 'Acronis True Image Product Line' started by peterfoxTI, Jun 21, 2004.

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  1. peterfoxTI

    peterfoxTI Registered Member

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    If I defragment my hard disk between taking incremental images, will the resulting image file be smaller or larger?
     
  2. tazdevl

    tazdevl Registered Member

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    Neither, defragging does not increase or decrease file size.
     
    Last edited: Jun 22, 2004
  3. peterfoxTI

    peterfoxTI Registered Member

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    So you are saying that if I defragment my hard disk before running incremental image, the image size would be the same as if I choose to not defragment?
     
  4. tazdevl

    tazdevl Registered Member

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    Yes.

    Defragging does not compress files. It basically pulls together loose bits of data on your hard drive into a more coherent form. Means the drive seeks less, so your drive performance improves.

    Compression is built into True Image, very difficult to compress what has already been compressed and maintain image integrity i.e not have errors when you restore.

    To better understand how defragmenting works, I'd suggest a search on www.google.com.

    I'll start you on your journey.
    http://computer.howstuffworks.com/hard-disk.htm
     
    Last edited: Jun 22, 2004
  5. peterfoxTI

    peterfoxTI Registered Member

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    Speaking of education. Acronis True Image 7.0 User’s Guide says:

    "The unique technology developed by Acronis and implemented in Acronis True
    Image allows you to create exact, sector-by-sector disk images and restore their content directly from Windows without the reboots typical for similar products."

    "Acronis True Image can create incremental images. These images that contain only those disk sectors that changed after image creation."

    As far as I know, defragmentation process reallocates data so it can be read faster. Thus it rearranges content of data kept in various clusters on the disk. That leads to sometimes massive changes in data sectors on the hard drive, without changing content of files.
    Since TI is sector based, that should lead to a much larger incremental image file size if defregmentation was performed. Without defragmentation, there wouldn't be that many sector data changes.
    (and compression has nothing to do with that.)
     
  6. tazdevl

    tazdevl Registered Member

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    I think I misunderstood your question then. I was under the impression you were asking about a defrag after incremental.

    You are right, this is a known issue with TI 7.0. It will be bigger.

    To be honest, I'm about ready to return it and go back to DI 7.0, which despite the fact that its 18 months old, has better chipset support, can be run out of windows as well (without reboots), suports direct writing to DVD and doesn't have the incremental problems TI 7.0 does.

    Shame because it has the potential to be a great product if they had someone fairly sharp managing the roadmap.

    I do feel sorry for Anton. I think he does a great job here, but if you don't have intelligent people in the Product Management/Development organization bringing well designed products to market, not much he can do.
     
  7. peterfoxTI

    peterfoxTI Registered Member

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    To confirm that I have performed a test on my desktop (10GB disk, 4.5GB used).

    Base full image (normal compression) - 2.45GB
    Restarted, shutdown desktop, incremental image - 22MB (not bad)
    Restarted, defragged, shutdown desktop, incremental image - 1.35GB

    Advise: DO NOT defrag your hard disk between incremental images.
     
  8. tazdevl

    tazdevl Registered Member

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    Tough to do if you're running an automated defragger like Diskeeper. :D

    Anton, I think it's time you beat the developers over their heads for being knuckleheads.
     
    Last edited: Jun 22, 2004
  9. Acronis Support

    Acronis Support Acronis Support Staff

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    Hello --

    Actually, it is *inevitable* that after defragmentation the incremental image will become bigger. It's just the result of the way how sector-by-sector backup products operate... I believe it's hard to do anything about it, but I'll consult our developers on that matter.

    Thank you.

    --
    Best regards,
    Anton Gromov

    Acronis, Inc.
    395 Oyster Point Blvd. Suite 213
    South San Francisco
    CA 94080 USA
    http://www.acronis.com/

    Acronis... Compute with confidence
     
  10. tazdevl

    tazdevl Registered Member

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    Peter and others (including myself) on this forum have a valid architectural issue with the product.

    What's the point of offering incremental backups in your product if the imcremental image is nearly the size of the primary image (assuming you defrag in between the first image and incremental image)? The whole idea behind an incremental image is to track changes and save space. You cannot ask customers to not defrag their computers.

    So where is the utility in the feature other than being able to claim your product can, albeit in a potentially bloated manner, make an incremental backup.
     
    Last edited: Jun 23, 2004
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