Pyston is a fork of CPython 3.8.8 with additional optimizations for performance. It is targeted at large real-world applications such as web serving, delivering up to a 30% speedup with no development work required.
We plan on explaining our techniques in more detail in future blog posts, but the main ones we use are:
- A very-low-overhead JIT using DynASM
- Quickening
- Aggressive attribute caching
- General CPython optimizations
- Build process improvements
We have some experimental docker images on DockerHub with Pyston pre-installed, you can quickly try out Pyston by doing
docker run -it pyston/pyston
You could also attempt to use this as your base image, and python will be provided by Pyston.
The default image contains quite a few libraries for compiling extension modules, and if you'd like a smaller image we also have a pyston/slim version that you can use.
These have not been heavily tested, so if you run into any issues please report them to our tracker.
Our current recommended way to see if your Python code is running on Pyston is to do hasattr(sys, "pyston_version_info").
Pyston is API compatible but not ABI compatible with CPython. This means that C extensions will work, but they need to be recompiled.
Typically with Python one will download and install pre-compiled packages, but with Pyston there are currently not pre-compiled packages available (we're working on that) so the compilation step will run when you install them. This means that you may run into problems installing packages on Pyston when they work on CPython: the same issues you would have trying to recompile these packages for CPython.
Many packages have build-time dependencies that you will need to install to get them to work. For example to pip install cryptography you need a Rust compiler, such as by doing sudo apt-get install rustc.
First do
git submodule update --init pyston/llvm pyston/bolt pyston/LuaJIT pyston/macrobenchmarks
Pyston has the following build dependencies:
sudo apt-get install build-essential ninja-build git cmake clang libssl-dev libsqlite3-dev luajit python3.8 zlib1g-dev virtualenv libjpeg-dev linux-tools-common linux-tools-generic linux-tools-`uname -r`
Extra dependencies for running the test suite:
sudo apt-get install libwebp-dev libjpeg-dev python3.8-gdbm python3.8-tk python3.8-dev tk-dev libgdbm-dev libgdbm-compat-dev liblzma-dev libbz2-dev nginx rustc time
Extra dependencies for producing Pyston debian packages and portable directory release:
sudo apt-get install dh-make dh-exec debhelper patchelf
For a build with all optimizations enabled (LTO+PGO) run:
make -j`nproc`
An initial build will take quite a long time due to having to build LLVM twice, and subsequent builds are faster but still slow due to extra profiling steps.
A symlink to the final binary will be created with the name pyston3
For a quicker build during development run:
make unopt -j`nproc`
the generated executable can be found inside build/unopt_install/
Running a python file called script.py with pyston can be easily done via:
make script_unopt
or
make script_opt