HFSC(8) Linux HFSC(8)
NAME
HFSC - Hierarchical Fair Service Curve's control under linux
SYNOPSIS
tc qdisc add ... hfsc [ default CLASSID ]
tc class add ... hfsc [ [ rt SC ] [ ls SC ] | [ sc SC ] ] [ ul SC ]
rt : realtime service curve
ls : linkshare service curve
sc : rt+ls service curve
ul : upperlimit service curve
o at least one of rt, ls or sc must be specified
o ul can only be specified with ls or sc
SC := [ [ m1 BPS ] d SEC ] m2 BPS
m1 : slope of the first segment
d : x-coordinate of intersection
m2 : slope of the second segment
SC := [ [ umax BYTE ] dmax SEC ] rate BPS
umax : maximum unit of work
dmax : maximum delay
rate : rate
For description of BYTE, BPS and SEC - please see UNITS section of
tc(8).
DESCRIPTION (qdisc)
HFSC qdisc has only one optional parameter - default. CLASSID specifies
the minor part of the default classid, where packets not classified by
other means (e.g. u32 filter, CLASSIFY target of iptables) will be en-
queued. If default is not specified, unclassified packets will be
dropped.
DESCRIPTION (class)
HFSC class is used to create a class hierarchy for HFSC scheduler. For
explanation of the algorithm, and the meaning behind rt, ls, sc and ul
service curves - please refer to tc-hfsc(7).
As you can see in SYNOPSIS, service curve (SC) can be specified in two
ways. Either as maximum delay for certain amount of work, or as a band-
width assigned for certain amount of time. Obviously, m1 is simply
umax/dmax.
Both m2 and rate are mandatory. If you omit other parameters, you will
specify linear service curve.
SEE ALSO
tc(8), tc-hfsc(7), tc-stab(8)
Please direct bugreports and patches to: <netdev@vger.kernel.org>
AUTHOR
Manpage created by Michal Soltys (soltys@ziu.info)
iproute2 31 October 2011 HFSC(8)