[!WARNING] The Blue Brain Project concluded in December 2024, so development has ceased under the BlueBrain GitHub organization. Future development will take place at: https://github.com/openbraininstitute/MultiscaleRun

MultiscaleRun

MultiscaleRun is a Python package to run brain cells simulation at different scales. It orchestrates the coupling between several brain simulators like Neuron and STEPS but also solvers like AstroVascPy for the cerebral blood flow. The package also embeds a Julia solver to simulate the astrocytes activity.

The Python package includes a program called multiscale-run that lets you run and analyze multiscale simulations from start to finish.

Dependencies

This Python package requires Python 3.8 or higher.

How to install MultiscaleRun?

Apart from supercomputers where MultiscaleRun may be provided as a module, the general way to install MultiscaleRun is via the pip utility:

pip install multiscale-run

How to use the MultiscaleRun executable?

The multiscale-run executable provides several commands to initialize, configure and execute simulations

Setup a new simulation

shell multiscale-run init /path/to/my-sim

This command creates the following files in /path/to/my-sim providing both the circuit, the configuration files, and the runtime dependencies:

• circuit_config.json: description of the circuit to simulate
• node_sets.json: subsets of cells acting as targets for different reports or stimulations. See also https://github.com/AllenInstitute/sonata/blob/master/docs/SONATADEVELOPERGUIDE.md#node-sets-file
• simulation_config.json: ties together the definition of the simulation on the circuit, see section Simulation Configuration below to have an understanding of the dedicated "multiscale_run" section.
• simulation.sbatch: An example of SLURM script to launch the simulation on BB5
• postproc.ipynb: An example of Jupyter notebook making use of the simulation results to build a report

The generated setup is ready to compute, but feel free to browse and tweak the JSON configuration files at will, especially the "multiscalerun" section of file `simulationconfig.json`

:ledger: See multiscale-run init --help for more information

Verify a simulation configuration

This command performs a series of check to identify common mistakes in the configuration. It is recommended to perform this operation before starting a simulation.

shell multiscale-run check [/path/to/my/sim]

Compute the simulation

On the current machine / allocation

shell multiscale-run compute [/path/to/my-sim]

:ledger: To use multiple ranks, use srun -n X multiscale-run compute where X is the number of ranks. Notice that steps requires this to be a power of 2.

:ledger: See multiscale-run compute --help for more information

:exclamation: You may need to load the intel-oneapi-mkl module on BB5 if not already loaded otherwise you will probably experience the following error when running the compute phase: libmkl_intel_thread.so.1: undefined symbol: omp_get_num_procs

Three more folders will be created during the simulation: * cache: it keeps some cached communication matrices, useful for subsequent runs * mesh: mesh files for steps. If the folder is missing a standard mesh will be generated Just In Time * RESULTS: the results of the simulation. Various data are recorded here in HDF5 files. The variables are per-neuron based. MultiscaleRun mimics the structure of Neurodamus result files so that they can be post-processed with the same method

:For efficiency reasons, MultiscaleRun result files are filled with 0s at the beginning of the simulation. Thus, if the simulation dies early, these files will be full of 0s for the time steps after the simulation died

On SLURM cluster:

sbatch simulation.sbatch

Other operations

Custom Neuron mechanisms

This operation clones the Neurodamus mod files library for local editing.

shell multiscale-run edit-mod-files [/path/to/my-sim]

Troubleshooting

The command build_neurodamus.sh mod may fail with the following error: => LINKING shared library ./libnrnmech.so /usr/bin/ld: /path/to/install_oneapi-2023.2.0-skylake/neuron-9.0.a15-lrspl6/lib/libnrniv.so: unable to initialize decompress status for section .debug_info /usr/bin/ld: /path/to/install_oneapi-2023.2.0-skylake/neuron-9.0.a15-lrspl6/lib/libnrniv.so: unable to initialize decompress status for section .debug_info /path/to/install_oneapi-2023.2.0-skylake/neuron-9.0.a15-lrspl6/lib/libnrniv.so: file not recognized: File format not recognized icpx: error: linker command failed with exit code 1 (use -v to see invocation) make: *** [/path/to/install_oneapi-2023.2.0-skylake/neuron-9.0.a15-lrspl6/bin/nrnmech_makefile:133: mech_lib_shared] Error 1 This happens because Neuron was built with Intel oneAPI compiler but the compiler is not available in the environment. Loading the proper module on BB5 may fix the issue module load unstable intel-oneapi-compilers

Convert BlueConfig to SONATA compatible JSON file

1. Setup a development environment with the multiscale-run virtualenv operation
2. Clone the bluepy-configfile repository
3. Go to the repository and execute: pip install .
4. In the BlueConfig (BC) of interest comment out the RunMode field, the Circuit GLIA section, the Projection NeuroGlia section, and the the Projection GlioVascular section.
5. Go back to the MultiscaleRun repo and run blueconfig convert-to-sonata /gpfs/bbp.cscs.ch/project/proj62/Circuits/O1/20190912_spines/sonata/circuit_config.json ngv.json user.target BlueConfig. The first argument, i.e. circuit_config, should point to an existing SONATA circuit config file, which can be found by searching the folder defined in CircuitPath field of the BlueConfig. The second argument is the name of the SONATA simulation config file to be created from the BlueConfig. The third argument is the path to an existing SONATA nodesets file, and the fourth argument is the BlueConfig that we want to convert.
6. Now the ngv.json can be used from the Jupyter notebook for the visualizations.

Profile MultiscaleRun script with ARM MAP

1. Load ARM MAP in the environment: module load arm-forge
2. Run the simulation: map --profile --output OUT.map srun [...] multiscale-run compute [/path/to/my-sim]
3. Open OUT.map with the Arm Forge Client (locally)

For more on how to use ARM MAP on BB5, please check this page.

Changelog

• Remove upload gitlab logs as the CI logs are used only internally.
• New vasculature-segment-based reports are available now. Postproc and docs have been updated as well to address these new functionalities.

0.8.2 - 2024-08-27

Project governance

• Open-source release on GitHub https://github.com/BlueBrain/MultiscaleRun
• Publication of the documentation on https://multiscalerun.rtfd.io
• Move some of the GitLab CI/CD tasks to GitHub workflows.

Bugfixes

• Add the command multiscale_run stats to retrieve some simple stats from the simulation.
• virtualenv was not setting correctly HOC_LIBRARY_PATH when called from a python environment itself.

0.8.1 - 2024-07-03

Bugfixes

• edit-mod-files was not working anymore because neurodamus changed the position of the mod folder. Updated.
• edit-mod-files was giving wrong suggestions since we should use build_neurodamus.sh mod --only-neuron now.

0.8 - 2024-06-04

Major Changes

• The configuration file has changed in the connections section:
  • you can specify where the connection takes place and if you want to write the connection results (vals) in the source simulator too.
  • matrices are now part of the op operation and can be used throughout the code.
  • A dest_simulator key is now required for every connection as connect_to keys do not dictate which simulator is the destination simulator anymore.
  • Previous simulation_config.json files must be adapted since backward compatibility is not possible. However, changes should be small and self-explanatory if a new template is compared to an old version (v 0.7, config_format: 2) of the configuration file.
• New thorough verification of the MultiscaleRun configuration in file simulation_config.json during the check and compute operations.

Internal Changes

• Improve memory usage of class multiscale_run.MsrConfig
• Add update_currents.sh in root for temporary storage. We still need to figure out where to put it or if we want to keep it at all. Sofia Farina and Alexis Arnaudon know more about this file.

0.7 - 2024-04-10

Major Changes

Rework of the config object and the config file

• The configuration file msr_config.json does not exist anymore. All the MultiscaleRun configurations have been merged into simulation_config.json in a new root section:multiscale_run. This is not yet SONATA. The configuration is in the same file but Neurodamus is not aware of it. [BBPP40-455].
• The configuration has changed significantly from 0.6. The documentation has now a dedicated page to explain how to use it.
• All the magic numbers in metabolism have been moved to the configuration or eliminated. For this reason, simulation behavior changed. Currently, neurons develop an ATP deficiency that breaks the simulations after a certain amount of time. This requires studies that will be incorporated in a future release.

Rework of metabolism

• All the magic numbers that were used as glue among the various simulators have been moved to the configuration file (simulation_config.json) or removed.
• Value checking before a metabolism time step can now be changed from the config file. For example you can now say that if a neuron has an ATP that is lower than 0.25 it should be kicked out of the simulation and the simulation needs to continue without it. More information on how to do it is available in the configuration documentation.
• The metabolism model and metabolism object are not connected with fixed numbers anymore. Thus, if you want to change the model just a change in the configuration file is required.

Rework of the connections among simulators

• Connections among simulators can now be changed programmatically from the configuration. Just after a simulator (called destination simulator) does an advance the connection manager loops over its connections, picks the source simulator and performs the connections. Currently there are 3 types of connections:
  • sum sums the values from the source and the destination in the destination simulator.
  • set sets the values from source into destination.
  • merge merges the two discording values $V{\text{source}}$ and $V{\text{destination}}$ using the formula: $V{\text{source}} + V{\text{destination}} - V{n-1} = Vn$. $V_n$ is then set in both source and destination. This is the only connection type that also changes the source. Notice that swapping source and destination is not exactly equivalent because the sync is performed after a destination advance.

Rework of the reporting

• The reporting structure has been changed significantly (mostly simplified and improved). However, these changes are mostly under the hood except for the changes in the configuration file. Consider reading the appropriate section in the documentation to know more MultiscaleRun reports.

Minor Changes

• Added documentation for the configuration file.
• Added docstrings in the code.
• bf -> bloodflow keyword change for simpler future development [BBPP40-440].
• Added type suggestions for function signatures in the code.
• Formatted docstrings for sphinx documentation.
• Updated postproc to handle the new configuration.
• Reworked the Python import statements and the initialization of the MPI library to fix possible hanging issues when MPI_Finalize was called.
• Add static analysis of the code in the continuous-integration process.

Bug Fixes

• Fix a bug in the pytest CI that made it pass even if some tests were failing
• Fix hanging simulations when an error is thrown [BBPP40-427] when MPI is used

0.6 - 2024-03-04

• virtualenv command:
  • Improvement: the command now installs spack pkg if necessary. There is no need to run spack commands manually anymore. [!104]
  • Fix issue when MultiscaleRun was loaded from BB5 module py-multiscale-run. [BBPP40-430]
• edit-mod-file command: load intel compilers module if required (!104)
• improved the documentation of the Python API

0.5.1 - 2024-02-07

• Fix: init with julia create was not pointing to the correct location

0.5 - 2024-01-29

• Improved README
• msr_config.json is a template now. Prepared for the bbp workflow
• base_path is now specified in the main config file. This is breaking change. Add to your msr_config.json file a field: "base_path": "."
• ndam is now forced to use RoundRobin

0.4 - 2024-01-19

• New commands:
  • edit-mod-files: Clone the Neurodamus mod files library for local editing
  • virtualenv: Create a Python virtual environment to ease development of MultiscaleRun Python package
• Fix possible program hang due to sensitive MPI initialization
• Improved README
• Added a section for spack environments
• Increased standard mesh refinement for ratV10 to not have ranks without tets (omega_h cannot handle them)
• Align to bbp workflow

0.3 - 2024-01-10

• new post-processing command creates an HTML report based on simulation results. Usage: multiscale-run post-processing [sim-path]. Use multiscale-run post-processing -h for more information.
• init command:
  • new option --no-check to skip the tests of Julia environment which lasts several minutes
  • new keys in msr_config.json:
  • config_format: an integer, the version of this file structure
  • msr_version: a string indicating the version of MultiscaleRun that created this config
• compute command: now creates a Neurodamus success file at the end of the simulation
• Compatibility notes for simulations created with previous versions of MultiscaleRun
  • rename directory julia_environment to .julia_environment
  • it is not possible to override the JSON configuration keys with environment variables.
• GitLab CI on BB5 now relies on spack

0.2 - 2023-12-14

• Rework reporting [BBPP40-402, BBPP40-407, BBPP40-410, BBPP40-411, BBPP40-415]

0.1 - 2023-11-30

First release of the code shipped as a Python package

Authors

Polina Shichkova, Alessandro Cattabiani, Christos Kotsalos, and Tristan Carel

Funding and Acknowledgments

The development of this software was supported by funding to the Blue Brain Project, a research center of the École polytechnique fédérale de Lausanne (EPFL), from the Swiss government’s ETH Board of the Swiss Federal Institutes of Technology.

Copyright (c) 2023-2024 Blue Brain Project/EPFL