MUSIC is an API allowing large scale neuron simulators using MPI internally to exchange data during runtime. MUSIC provides mechanisms to transfer massive amounts of event information and continuous values from one parallel application to another. Special care has been taken to ensure that existing simulators can be adapted to MUSIC. In particular, MUSIC handles data transfer between applications that use different time steps and different data allocation strategies.
This is the MUSIC pilot implementation.
The two most important components built from this software
distribution is the music library libmusic.a' and the music utility music'. A MUSIC-aware simulator links against the C++ library and
can be launched using mpirun together with the music utility as
described below. MUSIC can also be used from a C program using the
API in music-c.h.
MUSIC is distributed under the GNU General Public License v3.
MUSIC is written in C++ and makes use of the MPI message passing library. MUSIC has been tested with versions 1.2 and 1.3 of OpenMPI, mpich and on BG/L. A visualization tool `viewevents' can be built if the GLUT toolkit is installed.
MUSIC version 1.0 makes use of the "long long" data type supported by, for example, the GNU C++ compiler g++.
MUSIC can be built and installed using the generic installation instructions found in the file INSTALL. At the top of the source distribution directory, do:
./autogen.sh
./configure --prefix=
(On some UNIX distributions you might need to run `ldconfig' or define LD_LIBRARY_PATH:
export LD_LIBRARY_PATH=/usr/local/lib
for the music utility to find its library.)
A MUSIC co-simulation is specified in a configuration file given as the first argument to the music utility. The test subdirectory contains a collection of examples, for example:
cd test mpirun -np 4 /usr/local/bin/music demo.music
On some systems, this way of invoking a MUSIC co-simulation isn't supported. Se blow for an alternative method.
configure.ac contains mechanisms which try to identify which MPI implementation/environment is in use and, based on this, decide automagically which compiler, compilation flags and linking flags to use. To circumvent, pass variable definitions ro configure, e.g.:
./configure MPI_CXXFLAGS="-g -O3"
The variables are:
MPI_CXX The compiler to use for MPI code MPI_CXXFLAGS C++ compilation flags MPI_CFLAGS C compilation flags MPI_LDFLAGS Linking flags
MUSIC comes with Python bindings. By default, the configure script looks for a Python interpreter in the path. If you want to use a particular Python interpreter, you can specify the path to it using the option --with-python:
./configure --with-python=/my/bin/python
Python support can be disabled using:
./configure --without-python
When launching a set of applications in a co-simulation, MUSIC needs to go outside the MPI standard in two respects:
It needs to know the MPI process rank of the running process before calling MPI::Init.
It needs to extract the first argument given to the music utility before calling MPI::Init.
The configuration script tries to figure out which MPI distribution is installed and how to compiler MUSIC for that distribution. The subdirectory mpidep contains all non-standard code. If you are trying to port the MUSIC library to a new version of MPI, please supply new definitions for the functions getRank and getConfig in mpidep/mpidep.c. For more details, see the file PORTING in this directory.
In case the method of launching MUSIC described under "Getting started" above fails, there is an alternative method:
Let's assume that we want to launch application A with binary a and Na processes, and application B with binary b and Nb processes. These are listed in a standard MUSIC config file ab.music with block labels A and B. The standard way to launch these would be:
mpirun -np <Na+Nb> music ab.music
(where <Na+Nb> is a number). These can alternatively be launched in MPMD style as:
mpirun -np Na ./a --music-config ab.music --app-label A : -np Nb ./b --music-config ab.music --app-label B
The MUSIC manual and other information can be found on the MUSIC wiki:
https://github.com/INCF/MUSIC/wiki
Questions and requests can be sent to mdj@pdc.kth.se.
Bug reports should be submitted as issues on the MUSIC github page: