- Latest (GraalVM for JDK 21)
- Dev Build
- GraalVM for JDK 21
- GraalVM for JDK 20
- GraalVM for JDK 17
- GraalVM 22.3
- GraalVM 22.2
- GraalVM 22.1
- GraalVM 22.0
- GraalVM 21.3
- Java on Truffle
- LLVM Languages Reference
- Python Reference
- Jython Compatibility
- Operating System Interfaces
- Installing Packages
- Python Code Parsing and pyc Files
- Python Native Executables
- Python Standalone Applications
- Tooling Support for Python
- Ruby Reference
- R Reference
- WebAssembly Reference
GraalVM Python Runtime
GraalPy provides a Python 3.10 compliant runtime. A primary goal is to support PyTorch, SciPy, and their constituent libraries, as well as to work with other data science and machine learning libraries from the rich Python ecosystem.. GraalPy can usually execute pure Python code faster than CPython, and nearly match CPython performance when C extensions are involved. While many workloads run fine, any Python program that uses external packages could hit something unsupported. At this point, the Python implementation is made available for experimentation and curious end-users. See the FAQ for commonly asked questions about this implementation.
Installing GraalPy #
Linux and macOS #
The easiest way to install GraalPy on Linux and macOS platforms is to use pyenv, the Python version manager. For example, to install version 22.3.0, for example, run the following commands:
pyenv install graalpy-22.3.0 pyenv shell graalpy-22.3.0
Another option is to use Conda-Forge. To get an environment with the latest version of GraalPy, use the following command:
conda create -c conda-forge -n graalpy graalpy
Alternatively, download a compressed GraalPy installation file appropriate for your platform. For example, for Linux, download a file that matches the pattern graalpy-XX.Y.Z-linux-amd64.tar.gz. Uncompress the file and update your PATH variable as necessary. If you are using macOS Catalina or later, you may need to remove the quarantine attribute. To do this, run the following command:
sudo xattr -r -d com.apple.quarantine /path/to/GRAALPY_HOME
To try GraalPy with a full GraalVM, including support for Java embedding and interoperability with other languages, you can use the bundled releases from www.graalvm.org.
There is currently no installer for Windows. Instead, follow these instructions to build GraalPy from source.
Running Python #
The best way of using GraalPy is from a
venv virtual environment.
This generates wrapper scripts and makes the implementation usable from a shell as the standard Python interpreter.
To create a
venv virtual environment with GraalPy, run the following command in your project directory:
graalpy -m venv <venv-dir>
To activate the environment in your shell session run:
Several executables are available in the virtual environment, including
You can run simple Python commands or programs with the
graalpy [options] [-c cmd | filename]
For example, start the Python interactive shell from the command line using the command
graalpy, then enter the following line at the Python shell prompt (identified by
>>>), followed by CR.
>>> print("Hello World!")
You should see the output displayed directly, followed by the Python interactive shell prompt
Hello World! >>>
Alternatively, you can invoke a Python script. Copy the following content into a file named helloworld.py:
graalpy and pass the filename as an argument:
You should see the following output
Python Options #
GraalPy supports some of the same options as Python 3.10 as well as some additional options to control the underlying Python runtime, GraalVM’s tools, and the execution engine. These can be viewed using the following command:
graalpy --help --help:tools --help:languages
Native Image and JVM Runtime #
By default, GraalVM runs GraalPy from a binary, compiled ahead-of-time with Native Image, yielding faster startup time and lower footprint.
Although the ahead-of-time compiled binary includes the Python and LLVM interpreters, to interoperate with
other languages you must supply the
This instructs the launcher to run on the JVM instead of in Native Image mode.
Thus, you will notice a longer startup time.