mozilla rr setup for ruby

mozilla-rr-ruby.org

Setup

Install rr

# Install rr dependencies
sudo yum install git python2 ccache cmake make gcc gcc-c++ gdb libgcc glibc-devel libstdc++-devel zlib-devel python27-pexpect man-pages capnproto

# Compile/install capnproto if no package available
curl -O https://capnproto.org/capnproto-c++-0.6.1.tar.gz
tar zxf capnproto-c++-0.6.1.tar.gz
pushd capnproto-c++-0.6.1
./configure --prefix=/usr
make -j$(nproc) check
sudo make install
popd

# Compile/install rr
git clone https://github.com/mozilla/rr.git
pushd rr
mkdir obj
cd obj
PKG_CONFIG_PATH=/usr/lib/pkgconfig cmake -Ddisable32bit=ON ../
make -j$(nproc)
sudo make install
popd

# Enable perf paranoid
echo "kernel.perf_event_paranoid=1" | sudo tee -a /etc/sysctl.conf

# Install debuginfo
yum-config-manager --enable "amzn-main-debuginfo" --enable "amzn-updates-debuginfo"
sudo debuginfo-install glibc

# Optional, may not be needed: Re-add the debug info into binary
# sudo eu-unstrip -i -a -p 19069 -d out/

# If you want to 'rr record; rr pack' and 'rr replay' in a separate machine
# Get the cpu features from the machine (laptop etc) you want to 'rr replay'
rr cpufeatures
--disable-cpuid-features 0x80050440,0x40140400 --disable-cpuid-features-ext 0xffffd854,0xffffffff,0xf3ffffff --disable-cpuid-features-xsave 0xfffffffe

Setup the app

Instructions for setting up Ruby

# Re-compile Ruby with "-O0" etc if needed
sudo yum install gcc openssl-devel libyaml-devel libffi-devel readline-devel zlib-devel gdbm-devel ncurses-devel
wget https://github.com/ruby/ruby/archive/v2_2_5.tar.gz
tar xvf v2_2_5.tar.gz
pushd ruby-2_2_5
autoconf
./configure --prefix=/usr/local --disable-install-doc --disable-install-rdoc --enable-load-relative  optflags="-O0" debugflags="-ggdb3"
make -j$(nproc)
sudo make install
popd

#Reinstall the gems
sudo rm -rf /data/somepath/shared/bundler_gems
pushd /data/somepath/current
sudo gem install bundler -v=1.10.6
sudo su deploy
bundle install --without=test development --path=/data/somepath/shared/bundler_gems
popd

# Modify the app launch, for example:
# Edit the /usr/local/bin/ruby-with-env with
export _RR_TRACE_DIR=/rr_trace/
exec /usr/local/bin/rr record --disable-cpuid-features 0x80050440,0x40140400 --disable-cpuid-features-ext 0xffffd854,0xffffffff,0xf3ffffff --disable-cpuid-features-xsave 0xfffffffe "/usr/local/bin/ruby" "$@"
# Edit passenger.conf
#  Set "passenger_spawn_method" to "direct"
#  Set "passenger_max_pool_size" and "passenger_min_pool_size" values
#  Remove "passenger_memory_limit"
#  Set "passenger_start_timeout" to 3000


# Backing up rootfs
# rsync remote rootfs into local
sudo rsync --progress  --hard-links --compress --archive --acls --xattrs --verbose --rsh 'ssh -F /home/surki/.ssh/config -i /home/surki/.ssh/id_rsa'  --rsync-path='sudo rsync' --exclude={'/dev/*','/proc/*','/sys/*','/tmp/*','/run/*','/mnt/*','/media/*','/lost+found','/backup.tar.gz','/root/.cache/*','/lib/modules/*','/data/somepath/shared/cached-copy/*','/usr/src/*','/usr/local/share/.cache/*','/backup/*','/tmp/*','/data/somepath/releases/*','/data/somepath/shared/cached-copy/*','/var/*','/opt/*'} somemachine-i3metal:/ ./amzlinux_rootfs_new/ | tee /tmp/rsync.log

Or if you want to use tar + untar method: cd / && tar -cvpzf backup.tar.gz --exclude=/backup.tar.gz --exclude=/root/.cache --exclude=/usr/share --exclude=/lib/modules --exclude=/usr/lib/jvm --exclude=/data/somepath/shared/cached-copy --exclude=/usr/src --exclude=/usr/local/share/.cache --exclude=/backup --exclude=/tmp --exclude=/data/somepath/releases --exclude=/data/somepath/shared/cached-copy --exclude=/var --exclude=/opt --one-file-system /
sudo tar -xvpzf /path/to/backup.tar.gz -C amzlinux_rootfs --numeric-owner

Using rr

# Record

# To replay on the same machine
rr replay /rr_trace/ruby-0/ -- -ex 'handle SIGPIPE nostop noprint pass' -ex 'source /gdb_ruby.py'

# Replay in another machine under chroot
for f in /proc /sys /dev; do sudo mount --bind $f ./amzlinux_rootfs/$f; done
sudo chroot ./amzlinux_rootfs/ /bin/bash -c "rr replay /rr_trace/ruby-0/ -- -ex 'handle SIGPIPE nostop noprint pass' -ex 'source /gdb_ruby.py'"

# To disassemble a Ruby file
# ruby -e 'puts RubyVM::InstructionSequence.compile_file("/home/surki/.rvm/gems/ruby-2.2.7/gems/multi_json-1.12.1/lib/multi_json/options_cache.rb").disasm'

# To dump current heap from gdb
call rb_gc(), objspace_dump_all(0,0,0), rb_io_closed($172)