Allocation unit size

512 bytes or 4096 bytes or something else? which one is optimal? why?

peace!

I try to smile everyday but I can't... :smile:
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More about allocation unit size
  1. It depends on what file system you are using on your HDD's partition. You could be wasting space if you are not using NTFS. If you are using FAT32 in a 32k cluster, then you could be wasting space. (I'm assuming that your OS is W2k/XP) You may have to get a program called, "Partition Magic" to change your file system and reclaim wasted space.

    Here some old information in a PDF format on <A HREF="http://www.wdc.com/library/legacy/EIDE/fatfile.pdf" target="_new">FAT File System</A> in the simplest form, but very clear. Also, here is some info I posted in a later thread regarding cluster sizes. Hope this helps with your question.

    <b><font color=red>Default FAT32 cluster sizes:</b></font color=red>

    Partition Size (GB)******Sector Per Cluster******Cluster Size
    0.256 - 8.01****************** 8 **************** 4K
    8.02 - 16.02***************** 16 **************** 8K
    16.03 32.04 ***************** 32 *************** 16K
    > 32.04 ******************** 64 *************** 32K
    ________________________________________________________

    <b><font color=blue>Default NTFS Cluster Size:</b></font color=blue>

    Drive Size (MB)******Number of Sectors******Cluster Size
    512 ********************** 1 *************512 bytes
    513 - 1024 (1GB)*************2 ************1024 (1KB)
    1025 - 2048 (2GB)************4 ************2048 (2KB)
    2049 & larger *************** 8 ************4096 (4KB)


    <font color=purple><b>An average human brain weights aprox. 3lbs., but a thought weights a load.</font color=purple></b>
  2. 512 bytes is the sector size which is the smallest unit on the HD pyshically. A cluster is made up of 2 or more sectors, your 4096 number is 8 sectors or a 4k cluster =).

    I think the above post covered the rest.

    <font color=red>:</font color=red> <font color=white>:</font color=white> <font color=blue>:</font color=blue>
  3. so u meant 512 bytes is better rite? cuz i think smaller clusters are supposed to be better than bigger ones...thanks guys!

    I try to smile everyday but I can't... :smile:
  4. Not an issue with NTFS.

    <font color=red>:</font color=red> <font color=white>:</font color=white> <font color=blue>:</font color=blue>
  5. ok...then i'm cool with it...thanks!

    I try to smile everyday but I can't... :smile:
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