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diff --git a/upstream/archlinux/man8/tc-htb.8 b/upstream/archlinux/man8/tc-htb.8 new file mode 100644 index 00000000..7aa62615 --- /dev/null +++ b/upstream/archlinux/man8/tc-htb.8 @@ -0,0 +1,171 @@ +.TH HTB 8 "10 January 2002" "iproute2" "Linux" +.SH NAME +HTB \- Hierarchy Token Bucket +.SH SYNOPSIS +.B tc qdisc ... dev +dev +.B ( parent +classid +.B | root) [ handle +major: +.B ] htb [ default +minor-id +.B ] [ r2q +divisor +.B ] [ offload ] + +.B tc class ... dev +dev +.B parent +major:[minor] +.B [ classid +major:minor +.B ] htb rate +rate +.B [ ceil +rate +.B ] burst +bytes +.B [ cburst +bytes +.B ] [ prio +priority +.B ] [ quantum +bytes +.B ] + +.SH DESCRIPTION +HTB allows control of the outbound bandwidth on a given link. +It allows simulating simulating several slower links and to send different +kinds of traffic on different simulated links. In both cases, you have +to specify how to divide the physical link into simulated links and +how to decide which simulated link to use for a given packet to be sent. + +HTB shapes traffic based on the Token Bucket Filter algorithm +which does not depend on interface characteristics and so does not need to +know the underlying bandwidth of the outgoing interface. + +.SH SHAPING ALGORITHM +Shaping works as documented in +.B tc-tbf (8). + +.SH CLASSIFICATION +Within the one HTB instance many classes may exist. Each of these classes +contains another qdisc, by default +.BR tc-pfifo (8). + +When enqueueing a packet, HTB starts at the root and uses various methods to +determine which class should receive the data. + +In the absence of uncommon configuration options, the process is rather easy. +At each node we look for an instruction, and then go to the class the +instruction refers us to. If the class found is a barren leaf-node (without +children), we enqueue the packet there. If it is not yet a leaf node, we do +the whole thing over again starting from that node. + +The following actions are performed, in order at each node we visit, until one +sends us to another node, or terminates the process. +.TP +(i) +Consult filters attached to the class. If sent to a leafnode, we are done. +Otherwise, restart. +.TP +(ii) +If none of the above returned with an instruction, enqueue at this node. +.P +This algorithm makes sure that a packet always ends up somewhere, even while +you are busy building your configuration. + +.SH LINK SHARING ALGORITHM +FIXME + +.SH QDISC +The root of a HTB qdisc class tree has the following parameters: + +.TP +parent major:minor | root +This mandatory parameter determines the place of the HTB instance, either at the +.B root +of an interface or within an existing class. +.TP +handle major: +Like all other qdiscs, the HTB can be assigned a handle. Should consist only +of a major number, followed by a colon. Optional, but very useful if classes +will be generated within this qdisc. +.TP +default minor-id +Unclassified traffic gets sent to the class with this minor-id. +.TP +r2q divisor +Divisor used to calculate +.B quantum +values for classes. Classes divide +.B rate +by this number. Default value is 10. +.TP +offload +Offload the HTB algorithm to hardware (requires driver and device support). + +.SH CLASSES +Classes have a host of parameters to configure their operation. + +.TP +parent major:minor +Place of this class within the hierarchy. If attached directly to a qdisc +and not to another class, minor can be omitted. Mandatory. +.TP +classid major:minor +Like qdiscs, classes can be named. The major number must be equal to the +major number of the qdisc to which it belongs. Optional, but needed if this +class is going to have children. +.TP +prio priority +In the round-robin process, classes with the lowest priority field are tried +for packets first. + +.TP +rate rate +Maximum rate this class and all its children are guaranteed. Mandatory. + +.TP +ceil rate +Maximum rate at which a class can send, if its parent has bandwidth to spare. +Defaults to the configured rate, which implies no borrowing + +.TP +burst bytes +Amount of bytes that can be burst at +.B ceil +speed, in excess of the configured +.B rate. +Should be at least as high as the highest burst of all children. + +.TP +cburst bytes +Amount of bytes that can be burst at 'infinite' speed, in other words, as fast +as the interface can transmit them. For perfect evening out, should be equal to at most one average +packet. Should be at least as high as the highest cburst of all children. + +.TP +quantum bytes +Number of bytes to serve from this class before the scheduler moves to the next class. +Default value is +.B rate +divided by the qdisc +.B r2q +parameter. If specified, +.B r2q +is ignored. + +.SH NOTES +Due to Unix timing constraints, the maximum ceil rate is not infinite and may in fact be quite low. On Intel, +there are 100 timer events per second, the maximum rate is that rate at which 'burst' bytes are sent each timer tick. +From this, the minimum burst size for a specified rate can be calculated. For i386, a 10mbit rate requires a 12 kilobyte +burst as 100*12kb*8 equals 10mbit. + +.SH SEE ALSO +.BR tc (8) +.P +HTB website: http://luxik.cdi.cz/~devik/qos/htb/ +.SH AUTHOR +Martin Devera <devik@cdi.cz>. This manpage maintained by bert hubert <ahu@ds9a.nl> |