add swap on a rpi3

[Ian Lepore]

On Sat, 2018-07-14 at 19:28 +0200, Per olof Ljungmark wrote:
> 12.0-CURRENT #0 r336134 arm64 GENERIC on a rpi3 Cortex-A53
> 
> Can I add a swap "partition" somewhere below? I am booting from the
> SD
> card and run the system from an attached USB disk.
> 
> As I understand it, I cannot create a freebsd-swap partition/slice
> with
> the BSD/MBR scheme, but is there another way to create a reasonably
> large swap (>1G) under ARM?
> 
> =>      63  31116225  mmcsd0  MBR  (15G)
>         63      2016          - free -  (1.0M)
>       2079    102312       1  fat32lba  [active]  (50M)
>     104391  31008825       2  freebsd  (15G)
>   31113216      3072          - free -  (1.5M)
> 
> =>       0  31008825  mmcsd0s2  BSD  (15G)
>          0        57            - free -  (29K)
>         57  31008768         1  freebsd-ufs  (15G)
> 
> =>       63  125045361  da0  MBR  (60G)
>          63       2016       - free -  (1.0M)
>        2079     102312    1  fat32lba  [active]  (50M)
>      104391   83884089    2  freebsd  (40G)
>    83988480   41056944       - free -  (20G)
> 
> =>       0  83884089  da0s2  BSD  (40G)
>          0        57         - free -  (29K)
>         57  83884032      1  freebsd-ufs  (40G)
> 
> 

Looks like you've got some free space is on da0, so:

 gpart add -t freebsd -s <slicesize> -i 3 da0
 gpart create -s bsd da0s3
 gpart add -t freebsd-swap -s <swapsize> -i 2 da0s3

Now you have a swap parition at da0s3b (-i 2/partition b is sort of
traditional for freebsd swap partitions, but there's no real need for
it to be so).

You can make the size of da0s3 bigger than 1g, and then carve out just
1g of it for swap, leaving space to add ufs partitions in that slice
later if you want.

-- Ian