OpenSeesMPI

OpenSeesMPI uses the TclMPI package [1] to replicate the message passing functionality of OpenSeesMP [2], without requiring a parallel version of OpenSees.

Installation and Basic Use

• Install mpiexec
• Install Tcl
• Install OpenSees
• Install TclMPI
• Install OpenSeesMPI from this repository's latest release.

Then, OpenSeesMPI can be called as shown below, where $np represents the number of parallel processes, and $inputFile represents the Tcl input script.

OpenSeesMPI -n $np $inputfile

Advanced Use

Arguments up to the last argument or up to "--" are taken as mpiexec options. The remaining arguments are taken as the input file and the input arguments. If input arguments are desired, the option terminator "--" must be used.

OpenSeesMPI <$opt1 $opt2 ...> <--> $inputFile <$arg1 $arg2 ...>

Command Documentation

Functionality is compatible with OpenSeesMP, with a few additional features.

• The command getPID returns the integer rank of the process, using the TclMPI binding ::tclmpi::comm_rank.

  getPID

• The command getNP returns the number of parallel processes, using the TclMPI binding ::tclmpi::comm_size.

  getNP

• The command send either sends $data from the current process to process $pid, or broadcasts $data to all other processes (must be called from process 0), using the TclMPI bindings ::tclmpi::send and ::tclmpi::bcast.

  send <-pid $pid> $data

• The command recv either returns data sent from pid $pid (if $pid is "ANY", it will receive data from any process), or returns data broadcast from process 0, using the TclMPI bindings ::tclmpi::recv and ::tclmpi::bcast. Optionally, the received data can be stored in a variable with the $varName argument. Note that the $varName argument is optional with OpenSeesMPI but mandatory in OpenSeesMP.

  recv <-pid $pid> <$varName>

• The command barrier waits for all processes to reach the barrier, using the TclMPI binding ::tclmpi::barrier.

  barrier

More advanced MPI functionality is available with the TclMPI package, which is automatically loaded when using OpenSeesMPI. TclMPI commands are documented here: https://akohlmey.github.io/tclmpi/

Citations

1. Axel Kohlmeyer. (2021). TclMPI: Release 1.2 [Data set]. Zenodo. DOI: 10.5281/zenodo.5637677
2. Mckenna, F. (2011). OpenSees: A Framework for Earthquake Engineering Simulation. Computing in Science & Engineering, 13(4), 58–66. https://doi.org/10.1109/MCSE.2011.66

Acknowledgements

Thanks to Dr. Axel Kohlmeyer for making TclMPI available on Windows.

To Do:

• Provide Linux and Mac OS equivalents of OpenSeesMPI.bat