| 1 | #!/bin/bash |
| 2 | |
| 3 | CURDIR=$(dirname $0)/ |
| 4 | TESTDIR=$CURDIR/.. |
| 5 | source $TESTDIR/utils/tap.sh |
| 6 | |
| 7 | plan_tests 1 |
| 8 | |
| 9 | : ${ITERS:=10} |
| 10 | : ${NR_EVENTS:=7000000} |
| 11 | : ${NR_CPUS:=1} |
| 12 | |
| 13 | : ${TIME:="./$CURDIR/ptime"} |
| 14 | |
| 15 | : ${PROG_NOTRACING:="./$CURDIR/bench1 $NR_CPUS $NR_EVENTS"} |
| 16 | : ${PROG_TRACING:="./$CURDIR/bench2 $NR_CPUS $NR_EVENTS"} |
| 17 | |
| 18 | function signal_cleanup () |
| 19 | { |
| 20 | killall lttng-sessiond |
| 21 | } |
| 22 | |
| 23 | trap signal_cleanup SIGTERM SIGINT |
| 24 | |
| 25 | CMD_NOTRACING="$TIME '$PROG_NOTRACING >/dev/null 2>&1'" |
| 26 | CMD_TRACING="$TIME '$PROG_TRACING >/dev/null 2>&1'" |
| 27 | |
| 28 | for i in $(seq $ITERS); do |
| 29 | time_notrace[i]=$(sh -c "$CMD_NOTRACING") |
| 30 | done |
| 31 | |
| 32 | |
| 33 | lttng-sessiond -d --no-kernel |
| 34 | lttng -q create --snapshot |
| 35 | lttng -q enable-event -u -a |
| 36 | lttng -q start |
| 37 | |
| 38 | for i in $(seq $ITERS); do |
| 39 | time_trace[i]=$(sh -c "$CMD_TRACING") |
| 40 | done |
| 41 | |
| 42 | lttng -q stop |
| 43 | lttng -q destroy |
| 44 | killall lttng-sessiond |
| 45 | |
| 46 | pass "Trace benchmark" |
| 47 | |
| 48 | avg_delta=0 |
| 49 | for i in $(seq $ITERS); do |
| 50 | delta[$i]=$(echo "( ((${time_trace[$i]}) - (${time_notrace[$i]})) / $NR_EVENTS)" | bc -l) |
| 51 | avg_delta=$(echo "(${avg_delta} + ${delta[$i]})" | bc -l) |
| 52 | done |
| 53 | avg_delta=$(echo "(${avg_delta} / $ITERS)" | bc -l) |
| 54 | |
| 55 | std_dev=0 |
| 56 | for i in $(seq $ITERS); do |
| 57 | dev[$i]=$(echo "(( (${delta[$i]}) - (${avg_delta}) ) ^ 2)" | bc -l) |
| 58 | std_dev=$(echo "( (${std_dev}) + (${dev[i]}) )" | bc -l) |
| 59 | done |
| 60 | std_dev=$(echo "( (${std_dev}) / $ITERS )" | bc -l) |
| 61 | std_dev=$(echo "(sqrt(${std_dev}))" | bc -l) |
| 62 | |
| 63 | NS_PER_EVENT=$(echo "($avg_delta * 1000000000)" | bc -l) |
| 64 | # Remove fractions |
| 65 | NS_PER_EVENT=${NS_PER_EVENT%%.*} |
| 66 | |
| 67 | STD_DEV_NS_PER_EVENT=$(echo "($std_dev * 1000000000)" | bc -l) |
| 68 | STD_DEV_NS_PER_EVENT=${STD_DEV_NS_PER_EVENT%%.*} |
| 69 | |
| 70 | diag "Average tracing overhead per event is ${NS_PER_EVENT}ns, std.dev.: ${STD_DEV_NS_PER_EVENT}ns" |