Penguin
Recent Changes
Blame: tc-pfifo_fast(8)
EditPageHistoryDiffInfoLikePages
Annotated edit history of tc-pfifo_fast(8) version 4, including all changes. View license author blame.
Rev Author # Line
1 perry 1 PFIFO_FAST
2 !!!PFIFO_FAST
3 NAME
4 DESCRIPTION
5 ALGORITHM
6 PARAMETERS
7 BUGS
8 SEE ALSO
9 AUTHORS
10 ----
11 !!NAME
12
13
14 pfifo_fast - three-band first in, first out queue
15 !!DESCRIPTION
16
17
18 pfifo_fast is the default qdisc of each
19 interface.
20
21
22 Whenever an interface is created, the pfifo_fast qdisc is
23 automatically used as a queue. If another qdisc is attached,
24 it preempts the default pfifo_fast, which automatically
25 returns to function when an existing qdisc is
26 detached.
27
28
29 In this sense this qdisc is magic, and unlike other
30 qdiscs.
31 !!ALGORITHM
32
33
34 The algorithm is very similar to that of the classful
4 perry 35 tc-prio(8) qdisc. __pfifo_fast__ is like three
36 tc-pfifo(8) queues side by side, where packets can be
1 perry 37 enqueued in any of the three bands based on their Type of
38 Service bits or assigned priority.
39
40
41 Not all three bands are dequeued simultaneously - as long as
42 lower bands have traffic, higher bands are never dequeued.
43 This can be used to prioritize interactive traffic or
44 penalize 'lowest cost' traffic.
45
46
47 Each band can be txqueuelen packets long, as configured with
48 ifconfig(8) or ip(8). Additional packets
49 coming in are not enqueued but are instead
50 dropped.
51
52
4 perry 53 See tc-prio(8) for complete details on how TOS bits
1 perry 54 are translated into bands.
55 !!PARAMETERS
56
57
58 txqueuelen
59
60
61 The length of the three bands depends on the interface
62 txqueuelen, as specified with ifconfig(8) or
63 ip(8).
64 !!BUGS
65
66
67 Does not maintain statistics and does not show up in tc
68 qdisc ls. This is because it is the automatic default in the
69 absence of a configured qdisc.
70 !!SEE ALSO
71
72
73 tc(8)
74 !!AUTHORS
75
76
77 Alexey N. Kuznetsov,
78
79
80 This manpage maintained by bert hubert
81 ----
This page is a man page (or other imported legacy content). We are unable to automatically determine the license status of this page.