Re: Selecting the scheduler from boot menu

On Sat, 31 Jan 2026 12:39:07 -0800
Steve Kargl <kargls@comcast.net> wrote:

> On 1/31/26 12:25, Minsoo Choo wrote:
> > On Saturday, January 31st, 2026 at 3:22 PM, Steve Kargl <kargls@comcast.net> wrote:
> > 
> >>
> >>
> >> All,
> >>
> >> Is it possible modify the boot menu to select 4BSD or ULE
> >> during the boot process? I've looked at the code in
> >> src/stand/forth, but unfortunately the language is foreign
> >> to me. Currently, one boots into FreeBSD, checks the
> >> kern.sched.name, and then may need to edit /boot/loader.conf
> >> to change to the other scheduler, and then reboot.
> >>
> >> --
> >> steve
> > 
> > You can use `set variable_name="value"` in the loader prompt. To enter boot console, select "3. Escape to loader prompt" on boot screen.
> > 
> 
> Yes, of course, dropping to the loader prompt is possible.
> However, after an extended uptime, one might forget to do
> so; whereas the boot menu will jog the memory.  For example,
> if ULE is the default, then
> 
> 4. kernel with 4BSD scheduler
> 
> is a clear hint to choose the alternate loader.
> 
> -- 
> steve

Looks nice feature.

And if the list item can be dynamically generated as of
the list in sysctl value (not yet confirmed yet), it can be
a chance to notice any scheduler to be added or removed.
(Shouldn't work for scheduler updates, though.)

Regards.

-- 
Tomoaki AOKI    <junchoon@dec.sakura.ne.jp>