Add group hack for f19+

1 files changed, 127 insertions, 0 deletions

diff --git a/debloat.sh b/debloat.sh
new file mode 100755
index 0000000..2c78a0b
--- /dev/null
+++ b/debloat.sh
@@ -0,0 +1,127 @@
+#!/bin/bash
+# debloat.sh -	improves network latency by reducing excessive buffering 
+#		and offloads on common devices and enabling fq_codel.
+# Copyright 2012 M D Taht. Released into the public domain.
+
+# This script is presently targetted to go into 
+# /etc/network/ifup.d on debian derived systems
+
+LL=1 # go for lowest latency
+ECN=1 # enable ECN
+BQLLIMIT100=3000 # at speeds below 100Mbit, 2 big packets is enough
+BQLLIMIT10=1514 # at speeds below 10Mbit, 1 big packet is enough. 
+		# Actually it would be nice to go to just one packet
+QDISC=fq_codel # There are multiple variants of fq_codel in testing
+FQ_LIMIT="" # the default 10000 packet limit mucks with slow start at speeds 
+            # at 1Gbit and below. Somewhat arbitrary figures selected.
+
+[ -z "$IFACE" ] && echo error: $0 expects IFACE parameter in environment && exit 1
+[ -z `which ethtool` ] && echo error: ethtool is required && exit 1
+[ -z `which tc` ] && echo error: tc is required && exit 1
+# FIXME see if $QDISC is available. modprobe?
+
+# BUGS - need to detect bridges. 
+#      - Need filter to distribute across mq ethernet devices
+#      - needs an "undebloat" script for ifdown to restore BQL autotuning
+
+S=/sys/class/net
+FQ_OPTS=""
+#FQ_OPTS="FLOWS 2048 TARGET 5ms"
+
+[ $LL -eq 1 ] && FQ_OPTS="$FQ_OPTS quantum 500"
+[ $ECN -eq 1 ] && FQ_OPTS="$FQ_OPTS ecn"
+
+FLOW_KEYS="src,dst,proto,proto-src,proto-dst"
+# For 5-tuple (flow) fairness when the same device is performing NAT
+#FLOW_KEYS="nfct-src,nfct-dst,nfct-proto,nfct-proto-src,nfct-proto-dst"
+
+
+# Offloads are evil in the quest for low latency
+# And ethtool will abort if you attempt to turn off a
+# nonexistent offload.
+
+et() {
+(
+	ethtool -K $IFACE tso off
+	ethtool -K $IFACE gso off
+	ethtool -K $IFACE ufo off
+# Presently unknown if gro/lro affect latency much
+	ethtool -K $IFACE gro off
+	ethtool -K $IFACE lro off
+) 2> /dev/null
+}
+
+# Wifi is special in that how the queues work is pre-defined
+# to be voice, video, best effort and background
+
+wifi() {
+	tc qdisc add dev $IFACE handle 1 root mq 
+	tc qdisc add dev $IFACE parent 1:1 $QDISC $FQ_OPTS noecn
+	tc qdisc add dev $IFACE parent 1:2 $QDISC $FQ_OPTS
+	tc qdisc add dev $IFACE parent 1:3 $QDISC $FQ_OPTS
+	tc qdisc add dev $IFACE parent 1:4 $QDISC $FQ_OPTS noecn
+}
+
+# Hardware mq ethernet devs are special and need some sort of filter
+# attached to actually use in most cases. FIXME. (see tg3)
+
+mq() {
+	local I=1
+	tc qdisc add dev $IFACE handle 1 root mq 
+
+	for i in $S/$IFACE/queues/tx-*
+	do
+		tc qdisc add dev $IFACE parent 1:$(printf "%x" $I) $QDISC $FQ_OPTS
+		I=`expr $I + 1`
+	done
+	I=`expr $I - 1`
+	tc filter add dev $IFACE prio 1 protocol ip parent 1: handle 100 \
+		flow hash keys ${FLOW_KEYS} divisor $I baseclass 1:1
+}
+
+fq_codel() {
+	tc qdisc add dev $IFACE root $QDISC $FQ_OPTS $FQ_LIMIT
+}
+
+fix_speed() {
+local SPEED=`cat $S/$IFACE/speed` 2> /dev/null
+if [ -n "$SPEED" ]
+then
+	[ "$SPEED" = 4294967295 ] && echo "no ethernet speed selected. debloat estimate will be WRONG"
+	[ "$SPEED" -lt 1001 ] && FQ_LIMIT=1200
+	if [ "$SPEED" -lt 101 ]
+	then
+	[ $LL -eq 1 ] && et # for lowest latency disable offloads
+	BQLLIMIT=$BQLLIMIT100
+	FQ_LIMIT="limit 800"
+	[ "$SPEED" -lt 11 ] && BQLLIMIT=$BQLLIMIT10 && FQ_LIMIT="limit 400"
+	for I in /sys/class/net/$IFACE/queues/tx-*/byte_queue_limits/limit_max
+		do
+			echo $BQLLIMIT > $I
+		done
+	fi
+fi
+}
+
+fix_queues() {
+local QUEUES=`ls -d $S/$IFACE/queues/tx-* | wc -l | awk '{print $1}'`
+if [ $QUEUES -gt 1 ]
+then
+	if [ -x $S/$IFACE/phy80211 ] 
+	then
+		wifi
+	else
+		mq
+	fi
+else
+	fq_codel
+fi
+}
+
+
+tc qdisc del dev $IFACE root 2> /dev/null
+fix_speed
+fix_queues
+
+exit 0
+