Timesteps sometimes take negative time.
When we were obtaining performance results with SWIFT here, we noticed on the Xeon processors certain timesteps were outputting negative time taken:
131 1.023438e-03 7.812500e-06 262144 0 502.015 132 1.031250e-03 7.812500e-06 262144 0 508.461 133 1.039063e-03 7.812500e-06 262144 0 503.477 134 1.046875e-03 7.812500e-06 262144 0 506.939 135 1.054688e-03 7.812500e-06 262144 0 501.405 136 1.062500e-03 7.812500e-06 262144 0 **-1184.532** 137 1.070313e-03 7.812500e-06 262144 0 511.000
# Define the system of units to use internally. InternalUnitSystem: UnitMass_in_cgs: 1 # Grams UnitLength_in_cgs: 1 # Centimeters UnitVelocity_in_cgs: 1 # Centimeters per second UnitCurrent_in_cgs: 1 # Amperes UnitTemp_in_cgs: 1 # Kelvin # Parameters governing the time integration TimeIntegration: time_begin: 0. # The starting time of the simulation (in internal units). time_end: 2e-3 # The end time of the simulation (in internal units). dt_min: 1e-5 # The minimal time-step size of the simulation (in internal units). dt_max: 1e-5 # The maximal time-step size of the simulation (in internal units). # Parameters governing the snapshots Snapshots: basename: sedov # Common part of the name of output files time_first: 0. # Time of the first output (in internal units) delta_time: 1e-2 # Time difference between consecutive outputs (in internal units) # Parameters governing the conserved quantities statistics Statistics: delta_time: 1e-3 # Time between statistics output # Parameters for the hydrodynamics scheme SPH: resolution_eta: 1.2348 # Target smoothing length in units of the mean inter-particle separation (1.2348 == 48Ngbs with the cubic spline kernel). delta_neighbours: 0.1 # The tolerance for the targetted number of neighbours. CFL_condition: 0.1 # Courant-Friedrich-Levy condition for time integration. # Parameters related to the initial conditions InitialConditions: file_name: ./sedov.hdf5 # The file to read
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