Pathfinder

Pathfinder is a scalable and accurate application-level crash-consistency tool. It leverages representative testing: a new crash-state space reduction strategy based on the key observation is that the consistency of crash states is often correlated, even if those crash states are not identical. Pathfinder supports testing both POSIX-based applications and MMIO-based applications.

For more details, please refer to our OOPSLA 25 paper.

Directory structure

• cmake: Contains some custom CMake functions uses to build targets.
• deps: Project dependencies, notably PMDK.
• pathfinder: Core source code directory
• targets: These are the workloads Pathfinder tests. This contains source code and pathfinder-config.ini files, which tells Pathfinder how to test the targets.

Setup instructions

1. Install libraries

sudo apt update
sudo apt install cmake clang-13 llvm-13-dev libboost-all-dev libmlpack-dev libb64-dev libglib2.0-dev  libgtk2.0-dev zlib1g-dev  libc++-dev
sudo ln -s /usr/lib/gcc/x86_64-linux-gnu/11/libstdc++.so /usr/lib/x86_64-linux-gnu/libstdc++.so
sudo pip install wllvm

2. Set up the Pathfinder GitHub directory, including submodules.

git clone git@github.com:efeslab/Pathfinder.git
cd Pathfinder
git submodule init
git submodule update

Build instructions

cd Pathfinder #if you're not there already
mkdir build
cd build
cmake ..
make pathfinder-core -j

Note: the make process may generate some warnings (e.g., WARNING:Did not recognize the compiler flag "-dM"). This is expected (a consequence of using WLLVM for compilation).

Finding bugs

The targets in targets define a pathfinder-config.ini file to define run commands for testing.

To find bugs

cd Pathfinder/build
./pathfinder/pathfinder-core targets/<some target directory>/<some config file>

# example:
./pathfinder/pathfinder-core targets/leveldb-bug-0/pathfinder-config.ini

Writing a Pathfinder config file

See targets/leveldb-bug-0/pathfinder-config.ini for an example.

This is not a true INI file, but rather it is the file format parsed by boost commandline arguments. Each field can then be templated by Jinja2. Fields in {{ field }} are filled in with associated template values. The following are provided:

• build_root: the build directory
• pwd: the location of the config file in the build directory

Common Problems

• If ./pathfinder-core failed becasue of too many file opened, change the limit of file descriptors by ulimit -n 4096
• If libb64 not found, change root address in libb64, rebuild the directory, and remember to delete the posix_trace.so