git: 4e5c15f3107e - stable/15 - tuning.7: document schedulers knobs

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=4e5c15f3107e8c288bab3bfc5a9607c492e4c65d

commit 4e5c15f3107e8c288bab3bfc5a9607c492e4c65d
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-01-29 21:40:29 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-02-11 05:12:37 +0000

    tuning.7: document schedulers knobs
    
    (cherry picked from commit 0730a05cd383276ca8eedf295509e869ac9b88a0)
---
 share/man/man7/tuning.7 | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/share/man/man7/tuning.7 b/share/man/man7/tuning.7
index c03cce0aba0f..586b63c247a8 100644
--- a/share/man/man7/tuning.7
+++ b/share/man/man7/tuning.7
@@ -601,6 +601,32 @@ See the
 section in the
 .Xr sendfile 2
 manual page for details.
+.Sh SCHEDULERS
+.Fx
+allows having more than one scheduler specified in the kernel config,
+and the desired scheduler selected from them at boot time.
+Right now the options are:
+.Bl -tag -width SCHED_4BSD
+.It Cd SCHED_ULE
+The modern scheduler with O(1) thread selection behavior.
+.It Cd SCHED_4BSD
+Classic scheduler inherited from 4.x BSD.
+.El
+.Pp
+At least one option must be specified.
+.Cd SCHED_ULE
+is used by default if compiled in.
+.Pp
+The
+.Va kern.sched.available
+sysctl provides the comma-separated list of available (compiled in)
+schedulers.
+The
+.Va kern.sched.name
+loader tunable can be set to select the desired scheduler at boot time.
+The
+.Va kern.sched.name
+sysctl reports which scheduler is used.
 .Sh KERNEL CONFIG TUNING
 There are a number of kernel options that you may have to fiddle with in
 a large-scale system.