phpman > man > tc-hfsc(8)

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

       • at least one of rt, ls or sc must be specified
       • 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  tar‐
       get  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 al‐
       gorithm,  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  maxi‐
       mum  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.

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

       Please direct bugreports and patches to: <netdev AT vger.org>

AUTHOR
       Manpage created by Michal Soltys (soltys AT ziu.info)



iproute2                                   31 October 2011                                   HFSC(8)