Changes between Version 301 and Version 302 of doc/app/runtime_parameters

Timestamp:

Jun 5, 2019 10:56:10 AM (6 years ago)

Author:

raasch

Comment:

--

doc/app/runtime_parameters

@@ -480 +480 @@
 If data output is switched on (see [#data_output data_output], [#data_output_pr data_output_pr], [[../sppar#data_output_sp|data_output_sp]], and [#section_xy section_xy]), this parameter can be used to assign the temporal interval at which these data shall be output. Output can be skipped at the beginning of a simulation using parameter [#skip_time_data_output skip_time_data_output], which has zero value by default. The reference time is the beginning of the simulation, i.e. output takes place at times t = '''skip_time_data_output''' + '''dt_data_output''', '''skip_time_data_output''' + 2*'''dt_data_output''', '''skip_time_data_output''' + 3*'''dt_data_output''', etc. Since output is only done at the discrete time levels given by the time step used, the actual output times can slightly deviate from these theoretical values.\\\\
 Individual temporal intervals for the different output quantities can be assigned using parameters [#dt_do3d dt_do3d], [#dt_do2d_xy dt_do2d_xy], [#dt_do2d_xz dt_do2d_xz], [#dt_do2d_yz dt_do2d_yz], [#dt_domask dt_domask], [#dt_dopr dt_dopr], [[../sppar#dt_dosp|dt_dosp]], and [#dt_data_output_av dt_data_output_av].
+
+'''Warning:''' In case of parallel NetCDF I/O ([#netcdf_data_format netcdf_data_format] >= 5), setting small values for {{{dt_data_output}}} may result in HDF errors during model initialization, since internal NetCDF thresholds are execeeded. This especially can happen if large 3d arrays are output. 
 }}}
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@@ -682 +684 @@
 If output of 3d-volume data is switched on (see [#data_output data_output]), this parameter can be used to assign the temporal interval at which 3d-data shall be output. Output can be skipped at the beginning of a simulation using parameter [#skip_time_do3d skip_time_do3d], which has zero value by default. The reference time is the beginning of the simulation, i.e. output takes place at times t = '''skip_time_do3d''' + '''dt_do3d''', '''skip_time_do3d''' + 2*'''dt_do3d''', '''skip_time_do3d''' + 3*'''dt_do3d''', etc. The actual output times can deviate from these theoretical values (see [#dt_dopr dt_dopr]).\\\\
 Parameter [#do3d_at_begin do3d_at_begin] has to be used if an additional output is wanted at the start of a run (thus at the time t = 0 or at the respective starting times of restart runs).
+
+'''Warning:''' In case of parallel NetCDF I/O ([#netcdf_data_format netcdf_data_format] >= 5), setting small values for {{{dt_do3d}}} may result in HDF errors during model initialization, since internal NetCDF thresholds are execeeded. This especially can happen if large 3d arrays are output.
 }}}
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@@ -938 +942 @@
 
 Parallel file support (netcdf_data_format > 4) ''additionally'' requires to set the preprocessor switch {{{-D__netcdf4_parallel}}}.
+
+'''Warning:''' In case of parallel I/O ([#netcdf_data_format netcdf_data_format] >= 5), setting small values for [#dt_data_output dt_data_output] or [#dt_do3d dt_do3d] may result in HDF errors during model initialization, since internal NetCDF thresholds are execeeded. This especially can happen if large 3d arrays are output.
 }}}
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