How to check the partition alignment on an SSD drive?

As I understand it, for SSD it's important to have partitions starting at the proper offset (i.e. correctly aligned). How can I check this offset under Windows Vista?

Alexey Romanov

Posted 2010-04-18T13:36:32.280

Reputation: 1 698

Answers

Just run "C:\Program Files\Common Files\Microsoft Shared\MSInfo.exe", go to "Components > Storage > Disks" and find "Partition Starting Offset". It will be in bytes, divide the number by 512 to convert into sectors. On my SSD it is 1Mb (1 048 576 bytes), but as far as i know, 128k is enough.

On x64 you need to run msinfo32

Nishi

Posted 2010-04-18T13:36:32.280

Reputation: 545

1With Windows, 4k alignment is enough because NTFS does not have any periodic structure larger than the cluster size (unlike, say, ext2) – kinokijuf – 2015-08-05T12:03:18.567

2It's always msinfo32. Just type msinfo32 at a Run prompt (Windows-R). It's in your path. No need to go digging through directories. – Jamie Hanrahan – 2016-02-11T05:36:33.300

4On my Windows 7 x64 system it is C:\Program Files\Common Files\Microsoft Shared\MSInfo\msinfo32.exe – peter_mcc – 2011-12-21T21:53:07.183

On my Windows XP Pro x32 system it is C:\Program Files\Common Files\Microsoft Shared\MSInfo\msinfo32.exe too. Can't remember if it's part of the original XP install or not. – n611x007 – 2013-10-13T10:06:13.033

In Windows XP:

> diskpart -i <disk number>

should show HiddenSectors divisible by 64 and StartingOffest divisible by 32768

In Vista, 7, 8, 8.1 and 10:

> E:\Home>wmic partition get BlockSize, StartingOffset, Name, Index
BlockSize Index Name StartingOffset
512 0 Disk #1, Partition #0 1048576
512 1 Disk #1, Partition #1 53688139776

Alexey Romanov

Posted 2010-04-18T13:36:32.280

Reputation: 1 698

That wmic works even on Windows 10 – Csaba Toth – 2015-05-01T15:24:09.590

3diskpart doesn't seem to work that way in WinXP. can you give more details? – quack quixote – 2010-04-23T14:53:47.283

I had to do a convoluted series of commands on WinXP: diskpart > select disk 1 > list partition

Result:

<blockquote> DISKPART> list partition

Partition ### Type Size Offset ------------- ---------------- ------- ------- * Partition 1 Primary 49 GB 32 KB Partition 2 Extended 883 GB 49 GB Partition 3 Logical 883 GB 49 GB</blockquote> – Syclone0044 – 2011-11-09T19:50:35.310

You are right, but it does not work like that on Windows XP. There you can use diskpart:

diskpart -i (number of your ssd)

And you'll get geometry information and disk partition information.

I hope this helps.

Oscar

Posted 2010-04-18T13:36:32.280

Reputation: 41

I use the Paragon Alignment Tool, which comes with Paragon products, or can be bought seperately.

paradroid

Posted 2010-04-18T13:36:32.280

Reputation: 20 970

To check alignment, start "wmic" with admin rights, and enter command "partition get BlockSize, StartingOffset, Name, Index"

(wmic is available in Win7, possibly Vista)

jerryrogersomme

Posted 2010-04-18T13:36:32.280

Reputation: 11

diskpart.exe and diskpar.exe are separate utilities from Microsoft. What is given above works with diskpar.exe only:

diskpar -i x

x as the drive number. You cannot retrieve the offset using diskpart.exe. Use msinfo32.exe as described above

diskpart.exe started be be bundled with Windows 2003 and Vista. diskpar.exe was a standalone utility released at the time of Windows 2000. It still works with Windows 7 and 8.

Pierre de Grenoble

Posted 2010-04-18T13:36:32.280

Reputation: 11

WMI (wmic command) is available in Windows XP (SP3 or may be even early) (as a diskpart.exe btw). So in Windows XP you can use as Msinfo32 as Wmic to check offset. 1024K offset is the best choice for SDD and 4k disks or RAID.

DK21102

Posted 2010-04-18T13:36:32.280

Reputation: 11