HFSC(8)                 (31 October 2011)                 HFSC(8)

          HFSC - Hierarchical Fair Service Curve's control under linux

          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

     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

          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 bandwidth 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.

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     HFSC(8)                 (31 October 2011)                 HFSC(8)

          tc(8), tc-hfsc(7), tc-stab(8)

          Please direct bugreports and patches to:

          Manpage created by Michal Soltys (soltys@ziu.info)

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