qos-scripts update:
authorFelix Fietkau <nbd@openwrt.org>
Sat, 30 Jun 2007 02:34:03 +0000 (02:34 +0000)
committerFelix Fietkau <nbd@openwrt.org>
Sat, 30 Jun 2007 02:34:03 +0000 (02:34 +0000)
- rewrite the RED qdisc calculations and add some comments
this should fix the warnings about bursting (should also fix quirks with various linespeed settings)
- reduce the calculated overhead for upstream, while i'm at it...

SVN-Revision: 7782

package/qos-scripts/Makefile
package/qos-scripts/files/usr/lib/qos/generate.sh
package/qos-scripts/files/usr/lib/qos/tcrules.awk

index 676d4dd..181facd 100644 (file)
@@ -9,7 +9,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=qos-scripts
-PKG_VERSION:=1.1.1
+PKG_VERSION:=1.2.0
 PKG_RELEASE:=1
 
 PKG_BUILD_DIR := $(BUILD_DIR)/$(PKG_NAME)
index 844bd70..a2f7d71 100755 (executable)
@@ -261,7 +261,7 @@ start_interface() {
        for dir in up${halfduplex} ${download:+down}; do
                case "$dir" in
                        up)
-                               [ "$overhead" = 1 ] && upload=$(($upload * 98 / 100 - (32 * 128 / $upload)))
+                               [ "$overhead" = 1 ] && upload=$(($upload * 98 / 100 - (15 * 128 / $upload)))
                                dev="$device"
                                rate="$upload"
                                dl_mode=""
index d236b2d..7bef85b 100644 (file)
@@ -77,20 +77,41 @@ 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: "
+
+               # 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 (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"
                }
        }