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# set -x
SAMPLE_TIMES="2 5 10 20 30 45 60"
SAMPLE_TIMES="60 45 30 20 10 5 2"
FLOW_RATES="0 200 2000 20000 200000"
NETPERF="/home/raj/netperf2_trunk/src/netperf"
# these will be switch-specific
CPMIB="SFLOW-MIB::sFlowCpInterval.11.1.3.6.1.2.1.2.2.1.1.27.1"
FSMIB="SFLOW-MIB::sFlowFsPacketSamplingRate.11.1.3.6.1.2.1.2.2.1.1.27.1"
SFLOW_RRD="/tmp/counters/192.168.1.1/1/27/generic.rrd"
for sample in $SAMPLE_TIMES
do
LENGTH="300"
XGRID="--x-grid SECOND:5:SECOND:30:SECOND:30:0:%X"
# we want at least 10 sFlow samples
SAMPLES=`expr $LENGTH / $sample`
if [ $SAMPLES -lt 10 ]; then
LENGTH=`expr 10 \* $sample`
XGRID="--x-grid SECOND:10:SECOND:60:SECOND:60:0:%X"
fi
# configure the switch for the counter sampling interval
snmpset 192.168.1.1 $CPMIB i $sample
TWOXSAMPLE=`expr $sample \* 2`
for flow in $FLOW_RATES
do
# configure the switch for the flow sampling rate which is one per
# N on average, with some randomization if adhering to the sFlow
# spec.
snmpset 192.168.1.1 $FSMIB i $flow
# setup some variables
FILE_BASE="sample_${sample}_flow_${flow}"
NETPERF_BASE="raw_netperf_${FILE_BASE}"
NETPERF_RAW="${NETPERF_BASE}.out"
NETPERF_RRD="${NETPERF_BASE}.rrd"
# provide an indication of forward progress and status
echo "sample rate $sample flow rate 1 in $flow"
# start top
top -b -i > "top_${FILE_BASE}.out" &
TOP_PID=$!
# run our netperf test long enough to make sure we have as many
# sFlow samples as we wish even after we later skip the first two.
$NETPERF -t UDP_STREAM -H 192.168.1.3 -l `expr $LENGTH + $TWOXSAMPLE`\
-D 1 -c -C -- -m 1472 -s 64K -S 64K > $NETPERF_RAW
# stop top
kill -HUP $TOP_PID
# prepare to shove the interim results into an RRD
grep Interim $NETPERF_RAW > interims.tmp
# over what time interval do we have netperf interim results?
START=`head -1 interims.tmp | awk '{printf("%d",$10)}'`
END=`tail -1 interims.tmp | awk '{printf("%d",$10)}'`
# create an rrd for netperf starting at the beginning of that interval
rrdtool create netperf.rrd --step 1 --start $START \
DS:mbps:GAUGE:2:U:U RRA:AVERAGE:0.5:1:${LENGTH}
# shove those interim results into the netperf rrd
awk '{printf("rrdtool update netperf.rrd %f:%f\n",$10,$3)}' \
interims.tmp | sh
mv netperf.rrd $NETPERF_RRD
# extract the data from the sflow rrd to save it for posterity
rrdtool fetch $SFLOW_RRD AVERAGE --start $START --end $END \
> sflow_${FILE_BASE}.fetch
# now make the graph, trim-off the first two sFlow counter samples
# for better automagic scaling. the magic multiplier is how to go
# from mbps from netperf, which counts only payload, to octets on
# the wire assuming 8 bytes of UDP header 20 bytes of IP, 14 bytes
# of ethernet, 4 bytes of FCS and 1472 bytes of user payload
START=`expr $START + $TWOXSAMPLE`
# we don't like rrdtool's autoscaling
YMIN=`rrdtool graph /dev/null --start $START --end $END \
DEF:foo=${SFLOW_RRD}:ifOutOctets:AVERAGE \
CDEF:bar=foo,0.98,\* \
VDEF:bing=bar,MINIMUM \
PRINT:bing:"%6.2lf" | sed 1d`
YMAX=`rrdtool graph /dev/null --start $START --end $END \
DEF:foo=${SFLOW_RRD}:ifOutOctets:AVERAGE \
CDEF:bar=foo,1.02,\* \
VDEF:bing=bar,MAXIMUM \
PRINT:bing:"%6.2lf" | sed 1d`
# also consider the neterf results
NMIN=`rrdtool graph /dev/null --start $START --end $END \
DEF:foo=${NETPERF_RRD}:mbps:AVERAGE \
CDEF:baz=foo,128906.25,\* \
CDEF:bar=baz,0.98,\* \
VDEF:bing=bar,MINIMUM \
PRINT:bing:"%6.2lf" | sed 1d`
NMAX=`rrdtool graph /dev/null --start $START --end $END \
DEF:foo=${NETPERF_RRD}:mbps:AVERAGE \
CDEF:baz=foo,128906.25,\* \
CDEF:bar=baz,1.02,\* \
VDEF:bing=bar,MAXIMUM \
PRINT:bing:"%6.2lf" | sed 1d`
# I am certain someone will say dude use perl when they see this
INMIN=`echo $NMIN | awk '{printf("%d",$1)}'`
INMAX=`echo $NMAX | awk '{printf("%d",$1)}'`
IYMIN=`echo $YMIN | awk '{printf("%d",$1)}'`
IYMAX=`echo $YMAX | awk '{printf("%d",$1)}'`
# we wont sweat the fractional part
if [ $INMIN -lt $IYMIN ]; then
YMIN=$NMIN
fi
if [ $INMAX -gt $IYMAX ]; then
YMAX=$NMAX
fi
GRAPH="graph_${FILE_BASE}.svg"
SIZE="-w 1000 -h 400"
rrdtool graph $GRAPH --start $START --end $END \
--imgformat SVG \
-t "sFlow counter accuracy, average flow sample rate 1 in ${flow}" \
-v "Octets/s" \
$XGRID $SIZE --full-size-mode \
--upper-limit $YMAX \
--lower-limit $YMIN \
--rigid \
--alt-y-grid \
DEF:foo=${NETPERF_RRD}:mbps:AVERAGE \
DEF:bar=${SFLOW_RRD}:ifOutOctets:AVERAGE \
CDEF:baz=foo,128906.25,\* \
HRULE:124019607.84#000000:"Theoretical link-rate" \
LINE2:baz#FF0000:"netperf+headers at 1s intvl" \
LINE2:bar#00FF0080:"sFlow counters at ${sample}s intvl"
done
done
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