Input Parameters

Most Parthenon behavior is controlled via an input file, generally named parthinput.<problem-name>. Parameters in this file take the form param = value, with a particular type for each parameter set in the Parthenon code.

Parameters are split into blocks, denoted by bracketed names (<blockname>). All Parthenon-specific parameters are in blocks named <parthenon/x>. Below is an incomplete list of some parameters Parthenon accepts, split by block.

<parthenon/job>

General parthenon options such as problem name and parameter handling.

Option	Default	Type	Description
archive_parameters name	false none	string string	Produce a parameter file containing all parameters known to Parthenon. Set to true for an output file named parthinput.archive. Set to timestamp for a file with a name containing a timestamp. Name of this problem or initialization, prefixed to output files.

<parthenon/time>

Options related to time-stepping and printing of diagnostic data.

Option	Default	Type	Description
dt_ceil dt_factor dt_floor dt_force dt_init dt_init_force dt_min dt_min_cycle_limit dt_max dt_max_cycle_limit dt_user ncrecv_bdry_buf_timeout_sec ncycle_out ncycle_out_mesh nlim perf_cycle_offset tlim	none 2.0 none none none none none 10 none 1 none -1.0 1 0 -1 0 none	Real Real Real Real Real bool Real int Real int Real Real int int int int Real	The maximum allowed timestep. The maximum allowed relative increase of the timestep over the previous value. The minimum allowed timestep. Force the timestep to this value, ignoring all other conditions. The maximum allowed timestep during the first cycle. If set to true, force the first cycle’s timestep to the value given by dt_init. If the timestep falls below dt_min for dt_min_cycle_limit cycles, Parthenon fatals. The maximum number of cycles the timestep can be below dt_min. If the timestep falls below dt_max for dt_max_cycle_limit cycles, Parthenon fatals. The maximum number of cycles the timestep an be above dt_max. Set a global timestep limit. Timeout in seconds for the ReceiveBoundaryBuffers tasks. Disabed (negative) by default. Typically no need in production runs. Useful for debugging MPI calls. Number of cycles between short diagnostic output to standard out containing, e.g., current time, dt, zone-update/wsec. Default: 1 (i.e, every cycle). Number of cycles between printing the mesh structure to standard out. Use a negative number to also print every time the mesh was modified. Default: 0 (i.e, off). Stop criterion on total number of steps taken. Ignored if < 0. Skip the first N cycles when calculating the final performance (e.g., zone-cycles/wall_second). Allows to hide the initialization overhead in Parthenon. Stop criterion on simulation time.

<parthenon/mesh>

See the Adaptive Mesh Refinement documentation for details of the required parameters in <parthenon/mesh> and <parthenon/meshblock>.

Option	Default	Type	Description
nghost	2	int	Number of ghost cells for each mesh block on each side.

<parthenon/sparse>

See the Sparse implementation documentation for details.

Option	Default	Type	Description
alloc_threshold dealloc_count dealloc_threshold enable_sparse	1e-12 5 1e-14 true	float int float bool	Global (for all sparse variables) threshold to trigger allocation of a variable if cells in the receiving ghost cells are above this value. First deallocate a sparse variable if the dealloc_threshold has been met in this number of consecutive cycles. Global (for all sparse variables) threshold to trigger deallocation if all active cells of a variable in a block are below this value. If set to false, sparse variables will always be allocated, see also Run-time