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Last active December 24, 2023 05:25
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Quick steps of how to create a flame graph using perf

The prep-script.sh will setup the latest Node and install the latest perf version on your Linux box.

When you want to generate the flame graph, run the following (folder locations taken from install script):

sudo sysctl kernel.kptr_restrict=0
# May also have to do the following:
# (additional reading http://unix.stackexchange.com/questions/14227/do-i-need-root-admin-permissions-to-run-userspace-perf-tool-perf-events-ar )
sudo sysctl kernel.perf_event_paranoid=0

perf record -i -g -e cycles:u -- ~/sources/node/node --perf-basic-prof script.js

perf script | egrep -v "( __libc_start| LazyCompile | v8::internal::| Builtin:| Stub:| LoadIC:|\[unknown\]| LoadPolymorphicIC:)" | sed 's/ LazyCompile:[*~]\?/ /' | ~/sources/FlameGraph/stackcollapse-perf.pl > out.perf-folded

~/sources/FlameGraph/flamegraph.pl out.perf-folded > node-flame.svg

The data munging is to help expose the most important bits. There is still some play that I'm working with, but right now it seems to be working.

Alternatives:

perf script | egrep -v "( __libc_start|node::Start\(| LazyCompile | Builtin:| Stub:| LoadIC:|\[unknown\]| LoadPolymorphicIC:)" | ../FlameGraph/stackcollapse-perf.pl | grep "uv_run" > out.perf-folded

perf script | egrep -v "( __libc_start|node::Start\(| LazyCompile | v8::internal::| Builtin:| Stub:| LoadIC:|\[unknown\]| LoadPolymorphicIC:)" | ../FlameGraph/stackcollapse-perf.pl | grep "uv_run" > out.perf-folded
#!/bin/bash
sh /etc/lsb-release
wget -O - http://llvm.org/apt/llvm-snapshot.gpg.key|sudo apt-key add -
apt-add-repository "deb http://llvm.org/apt/${DISTRIB_CODENAME}/ llvm-toolchain-${DISTRIB_CODENAME} main"
apt-get update
apt-get -y upgrade
apt-get -y install make build-essential linux-tools-common elfutils libelf-dev flex bison libunwind8 libunwind8-dev libaudit-dev libdw-dev binutils-dev libnuma-dev libslang2-dev asciidoc llvm-3.6 clang-3.6 lldb-3.6 libllvm3.6 subversion libc6-dev-i386 libgtk2.0-dev libperl-dev python-dev git tmux nginx gdb apache2-utils
ln -s /usr/bin/clang-3.6 /usr/bin/clang
ln -s /usr/bin/clang++-3.6 /usr/bin/clang++
ln -s /usr/bin/lldb-3.6 /usr/bin/lldb
echo 'export CC=clang' > ~/.bash_aliases
echo 'export CXX=clang++' >> ~/.bash_aliases
echo 'export GYP_DEFINES="clang=1"' >> ~/.bash_aliases
. ~/.bash_aliases
chmod 777 /usr/share/nginx/html
ln -s /usr/share/nginx/html www
mkdir sources
cd sources
wget https://github.com/joyent/node/archive/v0.11.13.tar.gz
tar xvf v0.11.13.tar.gz
rm v0.11.13.tar.gz
mv node-0.11.13 node
cd node
./configure --gdb
make
make install
cd ~/sources
wget https://github.com/brendangregg/FlameGraph/archive/master.tar.gz
tar xvf master.tar.gz
rm master.tar.gz
mv FlameGraph-master FlameGraph
#cd ~/sources
#wget https://www.kernel.org/pub/linux/kernel/v3.x/linux-3.15.6.tar.gz
#tar xvf linux-3.15.6.tar.gz
#rm linux-3.15.6.tar.gz
#cd linux-3.15.6/tools/perf/
#make -f Makefile.perf install prefix=/usr
@Redsandro
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I'm interested in the function calls. There's a lot of module._something, garbage collection and _ZN2v88internal5Scope11LookupLocalEPKNS0_12AstRawStringE stuff in the graph together with function calls. Can I remove all the other stuff and only have the function calls?

@idx3d
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idx3d commented Nov 30, 2016

^^ +1 for the question above. Thx.

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