This patch updates qos-scripts to support fair traffic sharing using the
[openwrt/svn-archive/archive.git] / package / qos-scripts / files / usr / lib / qos / tcrules.awk
index d236b2df93e1528e0f44f409dcf1ae083d6b49e9..90b4212e72e9f569701389afc21046af39119670 100644 (file)
@@ -13,6 +13,8 @@ BEGIN {
        pktsize[n] = $4
        delay[n] = $5
        maxrate[n] = ($6 * linespeed / 100)
+       qdisc[n] = $7
+       filter[n] = $8
 }
 
 END {
@@ -77,26 +79,55 @@ END {
        # leaf qdisc
        avpkt = 1200
        for (i = 1; i <= n; i++) {
-               ql = int((avgrate[i] + linespeed) * 1024 / (8 * pktsize[i]))
                printf "tc qdisc add dev "device" parent 1:"class[i]"0 handle "class[i]"00: "
-               if (rtm1[i] > 0) {
+
+               # 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 " ql
+                       print "sfq perturb 2 limit "  limit
                } else {
-                       # non-rt class - use red
-                       min = int(maxrate[i] * 1024 / 8 * 0.05)
-                       if (min < avpkt) min = avpkt
-                       dqb = 8 * min;
-                       max = int(2.1*min)
-                       rburst = int((2*min + max) / (3 * avpkt))
+                       # 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 " dqb " probability 0.04 ecn"
+                       print "red min " min " max " max " burst " rburst " avpkt " avpkt " limit " limit " probability " prob " ecn"
                }
        }
        
        # filter rule
        for (i = 1; i <= n; i++) {
                print "tc filter add dev "device" parent 1: prio "class[i]" protocol ip handle "class[i]" fw flowid 1:"class[i] "0" 
+               filterc=1
+               if (filter[i] != "") {
+                       print " tc filter add dev "device" parent "class[i]"00: handle "filterc"0 "filter[i]
+                       filterc=filterc+1
+               }
        }
 }