1HFSC(8)                              Linux                             HFSC(8)
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NAME

6       HFSC - Hierarchical Fair Service Curve's control under linux
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SYNOPSIS

9       tc qdisc add ... hfsc [ default CLASSID ]
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11       tc class add ... hfsc [ [ rt SC ] [ ls SC ] | [ sc SC ] ] [ ul SC ]
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13       rt : realtime service curve
14       ls : linkshare service curve
15       sc : rt+ls service curve
16       ul : upperlimit service curve
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18       · at least one of rt, ls or sc must be specified
19       · ul can only be specified with ls or sc
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21       SC := [ [ m1 BPS ] d SEC ] m2 BPS
22              m1 : slope of the first segment
23              d  : x-coordinate of intersection
24              m2 : slope of the second segment
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26       SC := [ [ umax BYTE ] dmax SEC ] rate BPS
27              umax : maximum unit of work
28              dmax : maximum delay
29              rate : rate
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31       For  description  of  BYTE,  BPS  and SEC - please see UNITS section of
32       tc(8).
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DESCRIPTION (qdisc)

35       HFSC qdisc has only one optional parameter - default. CLASSID specifies
36       the  minor part of the default classid, where packets not classified by
37       other means (e.g. u32 filter, CLASSIFY  target  of  iptables)  will  be
38       enqueued.  If  default  is  not specified, unclassified packets will be
39       dropped.
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DESCRIPTION (class)

42       HFSC class is used to create a class hierarchy for HFSC scheduler.  For
43       explanation  of the algorithm, and the meaning behind rt, ls, sc and ul
44       service curves - please refer to tc-hfsc(7).
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46       As you can see in SYNOPSIS, service curve (SC) can be specified in  two
47       ways. Either as maximum delay for certain amount of work, or as a band‐
48       width assigned for certain amount of  time.  Obviously,  m1  is  simply
49       umax/dmax.
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51       Both  m2 and rate are mandatory. If you omit other parameters, you will
52       specify linear service curve.
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SEE ALSO

55       tc(8), tc-hfsc(7), tc-stab(8)
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57       Please direct bugreports and patches to: <netdev@vger.kernel.org>
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AUTHOR

60       Manpage created by Michal Soltys (soltys@ziu.info)
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64iproute2                        31 October 2011                        HFSC(8)