Lines Matching full:service
3 tc-hfcs \- Hierarchical Fair Service Curve
7 HFSC \- \fBHierarchical Fair Service Curve\fR was first presented at
26 minimize any discrepancy between the service curve and the actual amount of
27 service provided during linksharing
32 using nonlinear service curves (more about what it actually is later). This is
40 you might end with unusual situations, if you define service curves carelessly
44 situations where it's either not possible to guarantee service of all curves at
48 create a leaf class w/o realtime service, and in such case \- the caveats will
59 SC \- service curve
64 To understand how HFSC works, we must first introduce a service curve.
66 service (allowed or allocated amount of bandwidth) by some specific point in
68 allowed to transfer not less than the amount specified by its service curve \-
69 then service curve is not violated.
79 ability to "look back", so if during current active period service curve is violated, maybe it
92 Here 'w' denotes the amount of service received during some time period between t0
105 Consider \fB(a)\fR \- if the service received during both periods meets
107 period ? If the amount of service received during the 1st period is bigger
108 than the service curve, then it might compensate for smaller service during
117 when should we start transferring packets, so a service curve of a class is not
118 violated. Or rephrasing it: How much X() amount of service should a session
119 receive by time t, so the service curve is not violated. Function X() defined
127 service curve assigned to a class
137 HFSC uses either linear, or two\-piece linear service curves. In case of
152 service curve, \fIbut in case of a convex curve, uses its 2nd slope only.\fR
156 (dt\~=\~D^(\-1)(w+l), where \&'l' is packet's length). Based on RT service
162 (vt\~=\~V^(\-1)(w)). Based on LS service curve.
166 as well (ft\~=\~F^(\-1)(w)). Based on UL service curve.
169 Be sure to make clean distinction between session's RT, LS and UL service
180 Interface 10mbit, two classes, both with two\-piece linear service curves:
196 concave service curve is just like D(), but for the RT convex service curve \-
197 it's constructed using \fIonly\fR RT service curve's 2nd slope (in our example
219 scheduling. If you use UL service curve its F() will be updated as well (UL
220 service curve is an extension to LS one \- see \fBUPPERLIMIT CRITERION\fR
223 Anyway \- careless specification of LS and RT service curves can lead to
225 the case in HFSC paper where LS and RT service curves couldn't be specified
236 classes with simple linear 1mbit service curves will get the same treatment
255 presented in previous section and is caused by non\-linearity of service
258 either it's impossible to guarantee service curves and satisfy fairness
281 and/or it's impossible to guarantee service curves of all classes at the same
313 violated fairness in the A subtree and set A2's service curve to 0, A1 would
323 from F(), which is based on UL service curve. As you can see, it's role is
325 can't specify UL service curve without LS one.
327 Main purpose of UL service curve is to limit HFSC to bandwidth available on the
331 linear UL service curve to available bandwidth \- and then creating your class
332 structure from that class downwards. Of course, you're free to add UL service
335 Important part about UL service curve is, that whenever at some point in time
356 to UL service curve in place, C would get at most 2.5mbit, and A would get the
371 Separate service curves for LS and RT criteria can lead to certain traps,
374 specifying separate LS / RT service curves was not discussed.
385 bandwidth in 2:1 ratio, considering LS service curve (so in theory \- 6.66 and
401 times across class hierarchy. Leaf classes without RT service curves are
411 if extra speed is needed (e.g. due to latency), non linear service curves
416 You can quickly "workaround" it by making sure each leaf class has RT service
438 service curve is used to limit the speed at which LS criterion is allowed to
506 many timer interrupts. Example with 300mbit RT service curve on 1gbit link is
511 interface to begin with \- you will pretty much always want regular LS service
514 300mbit RT service curve (selected columns from mpstat \-P ALL 1):
523 So, in rare case you need those speeds with only RT service curve, or with UL
524 service curve \- remember about drawbacks.
