Re: Selecting the scheduler from boot menu

From: Mark Millard <marklmi_at_yahoo.com>
Date: Sat, 31 Jan 2026 20:53:35 UTC 
On 1/31/26 12:21, Steve Kargl 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.
> 

Are you asking because of needing to repeatedly switch back and forth?
Or is this about the one time setup for repeated booting using the same
scheduler? (Such might bias the reasonable answers/suggestions.)


FYI: it looks like . . .

Back on 2018-08-19, LOADER_DEFAULT_INTERP started to default to lua if
the lua loader is built (instead of using the forth or other loaders).
src/tree/stand/defs.mk has:

#
# Have a sensible default
#
.if ${MK_LOADER_LUA} == "yes"
LOADER_DEFAULT_INTERP?=lua
.elif ${MK_FORTH} == "yes"
LOADER_DEFAULT_INTERP?=4th
.else
LOADER_DEFAULT_INTERP?=simp
.endif
LOADER_INTERP?=${LOADER_DEFAULT_INTERP}

Of course, you may well have controlled which are built or which is used
of those that are built.


-- 
===
Mark Millard
marklmi at yahoo.com