Re: How to resize swap in NetBSD 10?

["Jonathan A. Kollasch" <jakllsch%kollasch.net@localhost>]

On Mon, Mar 17, 2025 at 06:37:42PM -0400, Tom Lane wrote:
> I have a macppc machine running NetBSD 10.1 that has been failing to
> run some larger programs.  dmesg showed things like
> 
> [ 1750816.967766] trap: pid 18392.18392 (perl): user write DSI trap @ 0xbc949000 by 0xfdc9ea88 (DSISR 0x42000000, err=12)
> [ 1750816.967766] UVM: pid 18392.18392 (perl), uid 1001 killed: out of swap
> 
> So I figured I'd better enlarge the swap partition from its 512MB
> size.  I deleted the swap and root partitions, remade them with the
> desired sizes, and reinstalled netbsd into the root.  That all seems
> to have gone according to plan, and the partition sizes are right
> according to pdisk:
> 
> $ sudo pdisk /dev/wd0c
> Edit /dev/wd0c -
> Command (? for help): p
> 
> Partition map (with 512 byte blocks) on '/dev/wd0c'
>  #:                type name      length   base      ( size )
>  1: Apple_partition_map Apple         63 @ 1        
>  2:           Apple_HFS boot       20480 @ 64        ( 10.0M)
>  3:     Apple_UNIX_SVR2 swap     4194304 @ 20544     (  2.0G) S1  SFS k0  (swap)
>  4:     Apple_UNIX_SVR2 root   112995392 @ 4214848   ( 53.9G) S0 RUFS k0  /
> 
> Device block size=512, Number of Blocks=117210240 (55.9G)
> DeviceType=0x0, DeviceId=0x0
> 
> But I was sad to find I still have only 512MB of swap space:
> 
> $ swapctl -l -h
> Device      Size     Used    Avail Capacity  Priority
> /dev/wd0b   512M       0B     512M     0%    0
> 
> I guess I need to do something to enlarge the swap space,
> but googling only yielded suggestions to use "mkswap"
> which doesn't exist on this system.
> 
> If anyone can point me in the right direction, it'd be
> much appreciated.

There's probably both a APM and a disklabel, and the disklabel is what
actually gets used.  Look at the apmlabel(8) man page for a possible way
to resolve this.