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
       enqueued.  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: <net...@vger.kernel.org>

AUTHOR
       Manpage created by Michal Soltys (sol...@ziu.info)



iproute2			31 October 2011			       HFSC(8)