1#! /bin/sh 2# 3# Copyright 2016 the V8 project authors. All rights reserved. 4# Use of this source code is governed by a BSD-style license that can be 5# found in the LICENSE file. 6# 7 8########## Global variable definitions 9 10# Ensure that <your CPU clock> / $SAMPLE_EVERY_N_CYCLES < $MAXIMUM_SAMPLE_RATE. 11MAXIMUM_SAMPLE_RATE=10000000 12SAMPLE_EVERY_N_CYCLES=10000 13SAMPLE_RATE_CONFIG_FILE="/proc/sys/kernel/perf_event_max_sample_rate" 14KERNEL_MAP_CONFIG_FILE="/proc/sys/kernel/kptr_restrict" 15CALL_GRAPH_METHOD="fp" # dwarf does not play nice with JITted objects. 16EVENT_TYPE=${EVENT_TYPE:=cycles:u} 17 18########## Usage 19 20usage() { 21cat << EOF 22usage: $0 <benchmark_command> 23 24Executes <benchmark_command> under observation by Linux perf. 25Sampling event is cycles in user space, call graphs are recorded. 26EOF 27} 28 29if [ $# -eq 0 ] || [ "$1" = "-h" ] || [ "$1" = "--help" ] ; then 30 usage 31 exit 1 32fi 33 34########## Actual script execution 35 36ACTUAL_SAMPLE_RATE=$(cat $SAMPLE_RATE_CONFIG_FILE) 37if [ "$ACTUAL_SAMPLE_RATE" -lt "$MAXIMUM_SAMPLE_RATE" ] ; then 38 echo "Setting appropriate maximum sample rate..." 39 echo $MAXIMUM_SAMPLE_RATE | sudo tee $SAMPLE_RATE_CONFIG_FILE 40fi 41 42ACTUAL_KERNEL_MAP_RESTRICTION=$(cat $KERNEL_MAP_CONFIG_FILE) 43if [ "$ACTUAL_KERNEL_MAP_RESTRICTION" -ne "0" ] ; then 44 echo "Disabling kernel address map restriction..." 45 echo 0 | sudo tee $KERNEL_MAP_CONFIG_FILE 46fi 47 48# Extract the command being perfed, so that we can prepend arguments to the 49# arguments that the user supplied. 50COMMAND=$1 51shift 1 52 53echo "Running..." 54perf record -R \ 55 -e $EVENT_TYPE \ 56 -c $SAMPLE_EVERY_N_CYCLES \ 57 --call-graph $CALL_GRAPH_METHOD \ 58 -i "$COMMAND" --perf_basic_prof "$@" 59