Specifying sizes in setup-storage

[Michael Goetze]

Thomas Lange wrote:
>>>>>> On Tue, 01 Sep 2009 19:22:20 +0200, Michael Goetze <mgoetze at mgoetze.net> said:
> 
>     > Hi,
>     > I'd like to create a swap partition which is 20% of the size of the
>     > disk, but at most 4GB. I tried the following setup-storage configuration:
> Which is the total size of your disk?
> 
>     > disk_config disk1 disklabel:msdos bootable:1
> 
>     > primary    /boot         192-256    ext3   rw
>     > primary    -             4G-        -      -
> 
>     > disk_config lvm
>     > vg vg0 disk1.2
>     > vg0-swap  swap          20%-4G      swap   rw
>     > vg0-root  /             80%-        ext3   rw,errors=remount-ro
> 
> IMO you defined to create a swap partition, which is at least 20% of
> your disk, but should not be bigger than 4GB. This may be
> self-contradictory for your disk size.

Sure, I understand why this configuration fails. What I don't understand
is how to get the desired effect. For instance, if I write 1G-4G, I get
3.4G on an 80G disk. But I want 4G in this case...

Regards,
Michael