document hfsc

mostly from Berk D. Demir <bdd at ieee.org> with tweaks by me
some nits and ok jmc@

1 files changed, 52 insertions, 6 deletions

diff --git a/share/man/man5/pf.conf.5 b/share/man/man5/pf.conf.5
index 280825bae13..bdce559c667 100644
--- a/share/man/man5/pf.conf.5
+++ b/share/man/man5/pf.conf.5
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: pf.conf.5,v 1.226 2003/04/29 10:36:34 dhartmei Exp $
+.\"	$OpenBSD: pf.conf.5,v 1.227 2003/04/29 12:44:14 henning Exp $
 .\"
 .\" Copyright (c) 2002, Daniel Hartmeier
 .\" All rights reserved.
@@ -542,8 +542,6 @@ assigned.
 mainly controls the time packets take to get sent out, while
 .Ar bandwidth
 has primarily effects on throughput.
-.It Ar hfsc
-Hierarchical Fair Service Curve.
 .It Ar priq
 Priority Queueing.
 .Ar Queues
@@ -561,6 +559,22 @@ Packets in the
 with the highest
 .Ar priority
 are processed first.
+.It Ar hfsc
+Hierarchical Fair Service Curve.
+.Ar Queues
+attached to an interface build a tree, thus each
+.Ar queue
+can have further child
+.Ar queues .
+Each queue can have a
+.Ar priority
+and a
+.Ar bandwidth
+assigned.
+.Ar Priority
+mainly controls the time packets take to get sent out, while
+.Ar bandwidth
+has primarily effects on throughput.
 .El
 .Pp
 The interfaces on which queueing should be activated are declared using
@@ -578,10 +592,10 @@ Currently supported values
 are
 .Ar cbq
 for Class Based Queueing,
-.Ar hfsc
-for the Hierarchical Fair Service Curve scheduler, and
 .Ar priq
-for Priority Queueing.
+for Priority Queueing and
+.Ar. hfsc
+for the Hierarchical Fair Service Curve scheduler.
 .It Ar bandwidth <bw>
 The maximum bitrate for all queues on an
 interface may be specified using the
@@ -703,6 +717,38 @@ supports an additional option:
 The queue can borrow bandwidth from the parent.
 .El
 .Pp
+.Pp
+The
+.Ar hfsc
+.Ar scheduler
+supports some additional options:
+.Bl -tag -width Fl
+.It Ar realtime <sc>
+The minimum required bandwidth for the queue.
+.It Ar upperlimit <sc>
+The maximum allowed bandwidth for the queue.
+.It Ar linkshare <sc>
+The bandwidth share of a backlogged queue.
+.El
+.Pp
+<sc> is an acronym for
+.Ar service curve .
+.Pp
+The format for service curve specifications is
+.Ar ( m1 , d , m2 ) . 
+.Ar m2
+controls the bandwidth assigned to the queue.
+.Ar m1
+and
+.Ar d
+are optional and can be used to control the initial bandwidth assignment.
+For the first
+.Ar d
+milliseconds the queue gets the bandwidth given as
+.Ar m1 ,
+afterwards the value given in
+.Ar m2 .
+.Pp
 Furthermore, with
 .Ar cbq
 and