From d5fc598d62e09bbe51c24c3823d512b80d662bca Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Wed, 16 May 2012 15:23:16 +0000 Subject: qos-scripts: replace sfq/red with fq_codel - massively improves latency under load SVN-Revision: 31759 --- package/qos-scripts/files/usr/lib/qos/tcrules.awk | 42 ++--------------------- 1 file changed, 2 insertions(+), 40 deletions(-) (limited to 'package/qos-scripts/files/usr/lib/qos/tcrules.awk') diff --git a/package/qos-scripts/files/usr/lib/qos/tcrules.awk b/package/qos-scripts/files/usr/lib/qos/tcrules.awk index 0021eaa7ce..a19b651920 100644 --- a/package/qos-scripts/files/usr/lib/qos/tcrules.awk +++ b/package/qos-scripts/files/usr/lib/qos/tcrules.awk @@ -79,47 +79,9 @@ END { # leaf qdisc avpkt = 1200 for (i = 1; i <= n; i++) { - printf "tc qdisc add dev "device" parent 1:"class[i]"0 handle "class[i]"00: " - - # RED parameters - also used to determine the queue length for sfq - # calculate min value. for links <= 256 kbit, we use 1500 bytes - # use 50 ms queue length as min threshold for faster links - # max threshold is fixed to 3*min - base_pkt=3000 - base_rate=256 - min_lat=50 - if (maxrate[i] <= base_rate) min = base_pkt - else min = int(maxrate[i] * 1024 / 8 * 0.05) - max = 3 * min - limit = (min + max) * 3 - - if (qdisc[i] != "") { - # user specified qdisc - print qdisc[i] " limit " limit - } else if (rtm1[i] > 0) { - # rt class - use sfq - print "sfq perturb 2 limit " limit - } else { - # non-rt class - use RED - - avpkt = pktsize[i] - # don't use avpkt values less than 500 bytes - if (avpkt < 500) avpkt = 500 - # if avpkt is too close to min, scale down avpkt to allow proper bursting - if (avpkt > min * 0.70) avpkt *= 0.70 - - - # according to http://www.cs.unc.edu/~jeffay/papers/IEEE-ToN-01.pdf a drop - # probability somewhere between 0.1 and 0.2 should be a good tradeoff - # between link utilization and response time (0.1: response; 0.2: utilization) - prob="0.12" - - rburst=int((2*min + max) / (3 * avpkt)) - if (rburst < 2) rburst = 2 - print "red min " min " max " max " burst " rburst " avpkt " avpkt " limit " limit " probability " prob " ecn" - } + print "tc qdisc add dev "device" parent 1:"class[i]"0 handle "class[i]"00: fq_codel" } - + # filter rule for (i = 1; i <= n; i++) { print "tc filter add dev "device" parent 1: prio "class[i]" protocol ip handle "class[i]"/0xff fw flowid 1:"class[i] "0" -- cgit v1.2.3