tests/benchmark/test_benchmark

   1 #!/bin/bash
   2 #
   3 # SPDX-License-Identifier: LGPL-2.1-only
   4
   5 CURDIR=$(dirname $0)/
   6 TESTDIR=$CURDIR/..
   7 source $TESTDIR/utils/tap.sh
   8
   9 plan_tests 1
  10
  11 : ${ITERS:=20}
  12 : ${NR_EVENTS:=7000000}
  13 : ${NR_CPUS:=1}
  14
  15 : ${TIME:="./$CURDIR/ptime"}
  16
  17 : ${PROG_NOTRACING:="./$CURDIR/bench1 $NR_CPUS $NR_EVENTS"}
  18 : ${PROG_TRACING:="./$CURDIR/bench2 $NR_CPUS $NR_EVENTS"}
  19
  20 function signal_cleanup ()
  21 {
  22         killall lttng-sessiond
  23 }
  24
  25 trap signal_cleanup SIGTERM SIGINT
  26
  27 CMD_NOTRACING="$TIME '$PROG_NOTRACING >/dev/null 2>&1'"
  28 CMD_TRACING="$TIME '$PROG_TRACING >/dev/null 2>&1'"
  29
  30 time_notrace=0
  31 for i in $(seq $ITERS); do
  32         if [[ $EUID -eq 0 ]]; then
  33                 echo 3 >/proc/sys/vm/drop_caches
  34         fi
  35         time_notrace="$time_notrace+$(sh -c "$CMD_NOTRACING")"
  36 done
  37
  38
  39 lttng-sessiond -d --no-kernel
  40 lttng -q create --snapshot
  41 lttng -q enable-event -u -a
  42 lttng -q start
  43
  44 time_trace=0
  45 for i in $(seq $ITERS); do
  46         if [[ $EUID -eq 0 ]]; then
  47                 echo 3 >/proc/sys/vm/drop_caches
  48         fi
  49         time_trace="$time_trace+$(sh -c "$CMD_TRACING")"
  50 done
  51
  52 lttng -q stop
  53 lttng -q destroy
  54 killall lttng-sessiond
  55
  56 pass "Trace benchmark"
  57 S_PER_EVENT=$(echo "( ($time_trace) - ($time_notrace) ) / $ITERS / $NR_EVENTS" | bc -l)
  58 NS_PER_EVENT=$(echo "$S_PER_EVENT * 1000000000" | bc -l)
  59 # Remove fractions
  60 NS_PER_EVENT=${NS_PER_EVENT%%.*}
  61
  62 diag "Average tracing overhead per event is ${NS_PER_EVENT}ns"