How to verify the alignment of a partition?

Discussion in 'backup, imaging & disk mgmt' started by Robin A., Jan 9, 2015.

  1. Robin A.

    Robin A. Registered Member

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    The "Windows-based" method is to obtain the “starting offset” of the partition (bytes) and divide it by 4096 (or 2048, or 1048576). If the result is an integer number, the partition is aligned. The offset can be obtained using the command

    wmic partition get Name, StartingOffset

    or using Msinfo32.exe (which yields the same results, as expected).

    The "third-party" method is to use AOMEI Partition Assistant or Minitool Partition Wizard or Image for Windows. The first two report directly if the partition is or isn´t aligned, no division required. IFW reports the starting LBA, which is then divided by 2048 to see if the result is an integer.

    But I have found contradictory results. For example, in one case the command above reports the Starting Offset for partition #3 as 146.897.108.480 bytes, which implies that the partition is not aligned. But both partition managers report that the partition is aligned, and IFW reports the LBA as 30.814.208, which also means that is aligned.

    So what happens? Is the “Windows-based” method not reliable?
     
  2. Minimalist

    Minimalist Registered Member

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  3. zapjb

    zapjb Registered Member

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  4. Stigg

    Stigg Registered Member

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  5. beethoven

    beethoven Registered Member

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    just checked my SSD (Samsung SSD 840 Evo) via the msinfo32 method and found the drive is not aligned. I then read this article http://lifehacker.com/5837769/make-...ned-for-optimal-solid-state-drive-performance on how to fix this. Not sure though if this is really necessary or how much improvement I might get. Also, I am using a dell (T5400) and remember that they sometimes have their own little quirks. When I migrated my harddrive to SSD I used Shadowprotect after resizing the disk with BIBM.
     
  6. markymoo

    markymoo Registered Member

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    Ignore what windows says, this is a reliable way with nice graphics. Get hold of AS SSD Benchmark

    When you run AS SSD it will immediately tell you in the left hand corner if you are aligned . Look at the second line in green if your aligned it say OK otherwise BAD, meaning not aligned.

    To align get hold of Mini Partition Wizard, Run it, Select the disk and click Align all partitions. Click Apply. That's it. Pc will restart to align all.
     
    Last edited: Jan 9, 2015
  7. Dave Burton

    Dave Burton Registered Member

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    I created a little script to check drive alignment under Windows Vista or later. Here it is:

    http://geeksalive.com/check_partition_alignment.zip
     
    Last edited by a moderator: Jan 11, 2016
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