"gpart add" falsely claiming "No space left on device"

Perry Hutchison perryh at pluto.rain.com
Sun Sep 11 03:40:52 UTC 2016

Warren Block <wblock at wonkity.com> wrote:
> Support for 8.1 ended over four years ago.  Improvements to man
> pages are not MFCed back to unsupported releases.

Nor would it matter (in this case) if they were, since I'm running
8.1 (not following 8-STABLE).

> > Alignment to 4k makes sense if the physical sector size is 4k (as
> > is often the case with newer disk drives) -- but 1M?  Seems a bit
> > much, which is why it would be useful for that page to include a
> > more detailed explanation.
> 1M is a useful value for several reasons.  A partition aligned with 1M 
> is aligned with all the smaller values.  It also better fits with the 
> larger internal block sizes used by SSDs and other flash devices.
> Starting the first data partition at 1M is a de facto standard and 
> provides a little additional insurance that some rock-stupid 
> partitioning tool will see the partition and not destroy it.
> At most, aligning to 1M wastes less than one meg of space.  Not one gig, 
> one meg.  On UEFI systems, you can even use that small amount of space 
> for an EFI partition.

Hopefully some of this explanation will find its way into that
disksetup.html page :)

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