/pyMIC

Primary LanguageC++BSD 3-Clause "New" or "Revised" LicenseBSD-3-Clause

DISCONTINUATION OF PROJECT.

This project will no longer be maintained by Intel.

Intel has ceased development and contributions including, but not limited to, maintenance, bug fixes, new releases, or updates, to this project.

Intel no longer accepts patches to this project.

If you have an ongoing need to use this project, are interested in independently developing it, or would like to maintain patches for the open source software community, please create your own fork of this project.

General Information

pyMIC is a Python module to offload computation in a Python program to the Intel Xeon Phi coprocessor. It contains offloadable arrays and device management functions. It supports invocation of native kernels (C/C++, Fortran) and blends in with Numpy's array types for float, complex, and int data types.

For more information and downloads please visit pyMIC's Github page: https://github.com/01org/pyMIC. You can find pyMIC's mailinglist at https://lists.01.org/mailman/listinfo/pymic. If you want to report a bug, please send an email to the mailinglist or file an issue at Github.

The pyMIC module is early code and is still under development. Please expect some bugs, strange behavior, and irritating error messages. We're working hard on getting all these things right, so we're more than happy to receive your input.

Contributors

  • Michael Klemm, Intel, Germany (maintainer)

  • Jussi Enkovaara, CSC, Finland (developer)

  • Freddie Witherden, Imperial College, United Kindom (developer)

Requirements

The requirements below describes the software packages that we have tested pyMIC with. Other versions and packages might also work.

Linux

The pyMIC module still has some special requirements for the build system. You will need to have the following software packages installed on your system:

Windows

Support for Windows is experimental and does not have a proper build system yet. You will to have the following software packages installed on your system:

Setting up the pyMIC module for Linux

Compilation

To compile pyMIC, please follow these steps carefully:

  • $pymic is the base directory of the pyMIC checkout/download.

  • Load the environment of the Intel Composer XE (if it has not been loaded yet):

    $> source /opt/intel/composerxe/bin/compilervars.sh intel64

  • Go to the pyMIC directory (replace $pymic with the right path for your system):

    $> cd $pymic
    
  • Use python ./setup.py build to compile the pyMIC module.

  • After successful compilation, type python ./setup.py install to install the module in the default place for Python modules.

Usage

To use the pyMIC module in a Python application on Linux, please follow these steps:

  • $pymic is the base directory of the pyMIC checkout/download

  • Load the environment of the Intel Composer XE (if it has not been loaded yet):

    $> source /opt/intel/composerxe/bin/compilervars.sh intel64
    
  • You can set OFFLOAD_REPORT=<level> to see the offloads that are triggered by pyMIC.

  • If you want to have even more fine-grained debugging output, set the environment variable PYMIC_DEBUG=<level>.

Please see the example codes in $pymic/examples and the API documentation for each pyMIC method on how to use the pyMIC module from your Python application.

Setting up the pyMIC Module for Windows

Compilation

The build system is based on a couple of Windows batch files. To compile pyMIC for Windows, please follow these steps:

  • %pymic% is the base directory of the pyMIC checkout/download

  • Start a command window with support for Intel compiler and 64-bit compilation.

  • Go the pyMIC directory (replace %pymic% with the right path for your system):

    > cd %pymic%
    
  • Load the pyMIC environment:

    > env.bat
    
  • Invoke the build:

    > make.bat
    
  • You should now find the Python extension pymic_libxstream.pyd and the shared object file liboffload_array.so in the pymic subdirectory.

Usage

To use the pyMIC module in a Python application, please follow these steps:

  • %pymic% is the base directory of the pyMIC checkout/download.

  • Start a command window with support for Intel compiler and 64-bit compilation.

  • Go the pyMIC directory (replace %pymic% with the right path for your system) and load the enviroment:

    > cd %pymic%
    > env.bat
    
  • Alternatively, set the Python search path, so that Python can find the pyMIC modules:

    > set PYTHONPATH=%PYTHONPATH%:%pymic%
    
  • You can set OFFLOAD_REPORT=<level> to see the offloads that are triggered by pyMIC.

  • If you want to have even more fine-grained debugging output, set the environment variable PYMIC_DEBUG=<level>.

Please see the example codes in %pymic%/examples and the API documentation for each pyMIC method on how to use the pyMIC module from your Python application.

Example Programs

There are a few examples programs that you can use for your first steps. You will find them in the $pymic/examples directory.

Setting up the Examples

pyMIC ships with a small set of example programs. The examples are not compiled and installed by default. Please follow these steps to run an example program:

  • $pymic is the base directory of the pyMIC checkout/download

  • Load the environment of the Intel Composer XE (if it has not been loaded yet):

    $> source /opt/intel/composerxe/bin/compilervars.sh intel64
    
  • Go to the directory of the example your are interested in, e.g., dgemm:

    $> cd $pymic/examples/dgemm
    
  • Type make in the directory.

Running the Examples

To run the examples, please make sure that the environment of Intel Composer XE and pyMIC have been loaded:

  • Linux:

    $> source /opt/intel/composerxe/bin/compilervars.sh intel64
    
  • Windows:

    > cd %pymic%
    > env.bat
    

After completing the setup steps for the environment, you should now be able to build the native code of the examples. For instance:

  • Linux:

    $> cd $PYMIC_BASE/examples/double_it
    $> make
    
  • Windows:

    > cd %PYMIC_BASE\examples\double_it
    > make.bat
    

The make command creates a shared object for the examples kernel code for native execution on the Intel(R) Xeon Phi(tm) Coprocessor. After this step has been completed, you can run the example code:

$> export PYMIC_LIBRARY_PATH=$PYMIC_LIBRARY_PATH:$PWD
$> python double_it.py

Side note: if the shared object created for the example depends on additional libraries (e.g., the examples dgemm and svd) you need to make sure that the directories hosting these libraries are visible on the coprocessor via NFS or have been installed to the /lib directory on the coprocessor's ramdisk.

Tracing & Debugging

If you are interested in what is going on inside the pyMIC module, you can choose from several options to get a more verbose output.

You can set the OFFLOAD_REPORT environment variable to request an offload report from the Intel offload runtime. Please have a loop at the article at https://software.intel.com/en-us/node/510366 to see what values are accepted for the environment variable and what effect they have.

The pyMIC module also supports more specific tracing and debugging.

Tracing

The pyMIC module can collect a trace of all performance relevant calls into the module. The trace consists of the called functions' name, timings, argument list, and (if collected) the source code location of the invocation.

To enable tracing, set PYMIC_TRACE=1 before launching the Python application. Shortly before the program finishes, the tracing information will be printed to stdout as Python maps and lists that have been converted to plain text. You can then run any desired analysis on the trace data.

For each trace record, pyMIC records its source code location of the invocation. This is called "compact" format (PYMIC_TRACE_STACKS=commpact). If the full call stack of the invocation is needed, PYMIC_TRACE_STACKS=full will collect the full call stack from the call site of a pyMIC function up to the top of the application code. You can turn of stack collection (to increase performance while tracing) by setting PYMIC_TRACE_STACKS=none.

Debugging

You can set the PYMIC_DEBUG environment variable to enable the debugging output of pyMIC. Here's the list of accepted values and what effect they have. Please note that higher levels include lower levels, that is, they increase verbosity of the output.

Level Effect
0 disable debugging output
1 show data transfers and kernel invocation
2 show allocation/deallocation of buffers
3 show argument conversions
5 show additional operations performed
10 extension module: data transfers
100 extension module: buffer management, kernel invocation
1000 extension module: function entry/exit