Re: kernel: warning: total configured swap (493567 pages) exceeds maximum recommended amount

From: bob prohaska <fbsd_at_www.zefox.net>
Date: Tue, 11 Nov 2025 01:40:49 UTC
On Mon, Nov 10, 2025 at 11:29:10PM +0000, void wrote:
> Hi,
> 
> On a newly installed
> FreeBSD-16.0-CURRENT-arm-armv7-GENERICSD-20251103-088ced14a69b-281661.img
> 
> unmodified settings 32GB mmcsd.
> 
> fstab entry for swap is:
> 
> /dev/label/growfs_swap  none            swap    sw              0       0
> 
> swap in top shows:
> 
> Swap: 1928M Total, 1928M Free
> 
> # sysctl kern.maxswzone
> kern.maxswzone: 0
> 
> ???
> 
> how to fix/should I fix?
I've not seen any recognizable benefit in heeding  that warning, but YMMV
I've two Pi2's with 3.6G of swap and one with 1.7G of swap. All misbehave
in the same way.

If using USB you could try something like (as root)
swapoff /dev/da0s2
gpart resize -i 2 -s 1700M /dev/da0s2
swapon /dev/da0s2

If using microSD I'd be wary of swap; some very mysterious file corruption
emerged on a Pi3 which had swap on the microSD. Not your situation, of course,
just a cautionary tale. 
 
FWIW there is a random collection of "notes to self" at
http://www.zefox.net/~fbsd/
It's poorly organized, out of date and at least partly wrong.

HTH,

bob prohaska

 
>