From: Vijay Subramanian Date: Mon, 4 Jun 2012 12:55:57 +0000 (+0000) Subject: tc-fq_codel: Add manpage X-Git-Tag: v3.5.0~15 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=65e472d967e5de73ef09ea447b5e91c14d0835f5;p=thirdparty%2Fiproute2.git tc-fq_codel: Add manpage This patch adds the manpage for the FQ_CoDel (Fair Queuing Controlled-Delay) AQM. Signed-off-by: Vijay Subramanian --- diff --git a/man/man8/Makefile b/man/man8/Makefile index 6d6242ec0..67938737f 100644 --- a/man/man8/Makefile +++ b/man/man8/Makefile @@ -6,7 +6,7 @@ MAN8PAGES = $(TARGETS) ip.8 arpd.8 lnstat.8 routel.8 rtacct.8 rtmon.8 ss.8 \ tc-tbf.8 tc.8 rtstat.8 ctstat.8 nstat.8 routef.8 tc-codel.8 \ tc-sfb.8 tc-netem.8 tc-choke.8 ip-tunnel.8 ip-rule.8 ip-ntable.8 \ ip-monitor.8 tc-stab.8 tc-hfsc.8 ip-xfrm.8 ip-netns.8 \ - ip-neighbour.8 ip-mroute.8 ip-maddress.8 ip-addrlabel.8 + ip-neighbour.8 ip-mroute.8 ip-maddress.8 ip-addrlabel.8 tc-fq_codel.8 all: $(TARGETS) diff --git a/man/man8/tc-fq_codel.8 b/man/man8/tc-fq_codel.8 new file mode 100644 index 000000000..8b43c1039 --- /dev/null +++ b/man/man8/tc-fq_codel.8 @@ -0,0 +1,108 @@ +.TH FQ_CoDel 8 "4 June 2012" "iproute2" "Linux" +.SH NAME +CoDel \- Fair Queuing (FQ) with Controlled Delay (CoDel) +.SH SYNOPSIS +.B tc qdisc ... fq_codel +[ +.B limit +PACKETS ] [ +.B flows +NUMBER ] [ +.B target +TIME ] [ +.B interval +TIME ] [ +.B quantum +BYTES ] [ +.B ecn +| +.B noecn +] + +.SH DESCRIPTION +FQ_Codel (Fair Queuing Controled Delay) is queuing discipline that combines Fair +Queuing with the CoDel AQM scheme. FQ_Codel uses a stochastic model to classify +incoming packets into different flows and is used to provide a fair share of the +bandwidth to all the flows using the queue. Each such flow is managed by the +CoDel queuing discipline. Reordering within a flow is avoided since Codel +internally uses a FIFO queue. + +.SH PARAMETERS +.SS limit +has the same semantics as +.B codel +and is the hard limit on the real queue size. +When this limit is reached, incoming packets are dropped. Default is 10240 +packets. + +.SS flows +is the number of flows into which the incoming packets are classified. Due to +the stochastic nature of hashing, multiple flows may end up being hashed into +the same slot. Newer flows have priority over older ones. This parameter can be +set only at load time since memory has to be allocated for the hash table. +Default value is 1024. + +.SS target +has the same semantics as +.B codel +and is the acceptable minimum +standing/persistent queue delay. This minimum delay is identified by tracking +the local minimum queue delay that packets experience. Default value is 5ms. + +.SS interval +has the same semantics as +.B codel +and is used to ensure that the measured minimum delay does not become too stale. +The minimum delay must be experienced in the last epoch of length .B interval. +It should be set on the order of the worst-case RTT through the bottleneck to +give endpoints sufficient time to react. Default value is 100ms. + +.SS quantum +is the number of bytes used as 'deficit' in the fair queuing algorithm. Default +is set to 1514 bytes which corresponds to the Ethernet MTU plus the hardware +header length of 14 bytes. + +.SS ecn | noecn +has the same semantics as +.B codel +and can be used to mark packets instead of dropping them. If +.B ecn +has been enabled, +.B noecn +can be used to turn it off and vice-a-versa. Unlike +.B codel, ecn +is turned on by default. + +.SH EXAMPLES +#tc qdisc add dev eth0 root fq_codel +.br +#tc -s qdisc show +.br +qdisc fq_codel 8002: dev eth0 root refcnt 2 limit 10240p flows 1024 quantum 1514 + target 5.0ms interval 100.0ms ecn + Sent 428514 bytes 2269 pkt (dropped 0, overlimits 0 requeues 0) + backlog 0b 0p requeues 0 + maxpacket 256 drop_overlimit 0 new_flow_count 0 ecn_mark 0 + new_flows_len 0 old_flows_len 0 + +#tc qdisc add dev eth0 root fq_codel limit 2000 target 3ms interval 40ms noecn +.br +#tc -s qdisc show +.br +qdisc fq_codel 8003: dev eth0 root refcnt 2 limit 2000p flows 1024 quantum 1514 +target 3.0ms interval 40.0ms + Sent 2588985006 bytes 1783629 pkt (dropped 0, overlimits 0 requeues 34869) + backlog 0b 0p requeues 34869 + maxpacket 65226 drop_overlimit 0 new_flow_count 73 ecn_mark 0 + new_flows_len 1 old_flows_len 3 + + +.SH SEE ALSO +.BR tc (8), +.BR tc-codel (8), +.BR tc-red (8) + +.SH AUTHORS +FQ_CoDel was implemented by Eric Dumazet. This manpage was written +by Vijay Subramanian. Please report corrections to the Linux Networking +mailing list .