Shrinking volumes

Sometimes, I find it useful to shrink volumes.  This happens about once every 2 or 3 years.  Since I do it so infrequently, I have to look it up every time.

In my experience, while you can do it from the GUI, it isn’t always successful.  Also, I have not ever seen it work to try and shrink it by the complete amount that is available to shrink.  My experiences are related to very large (larger than 1 TB) volumes.

To shrink via the command line, at an elevated prompt, do the following:

Diskpart – this is the disk management CLI

List volumes – this is the diskpart cmd that gives you a list of volumes (not to be confused with the list of disks

select volume <#> – this is how you select the volume that you want to work on, i.e. “select volume 2

shrink querymax – this tells you how much space can be trimmed off the volume.  There are several factors that affect this, but the primary things are how big the volume is to begin with, and where on that volume the un-movable system files  are located.

shrink desired=<size in MB> – this tells the volume to shrink by the amount of space given in MB.  I.e. “shrink desired=102400” will shrink the volume by 100GB.

shrink minimum=<size in MB> – this tells the volume to shrink by the amount specified, but only if it can shrink by that amount

You can use the minimum and desired together if you want.  You can also add a “NOWAIT” so that the prompt returns and you don’t have to wait to see the results.

Leave a comment

Your email address will not be published.