It is recommended that for each run of any component, all parameter
values are saved to the job database. This action allows you to inspect
the runs at any time to confirm that the components ran correctly or
to investigate when they ran incorrectly. It also allows results to be
reused in other jobs. However, saving all values can consume large amounts
of storage space. The Save general parameter values to the
database at runtime option reduces the amount of data saved
in memory if the database is disabled.
More specifically, you may choose not to save parameter values because:
-
The parameters are used only within their component. This includes unmapped
(constant) inputs, unmapped outputs, and parameters defined to be local
(i.e., they are not mapped to/from other components in the model).
-
The parameters receive their values at run time through data mappings
(so parameters in other components record those values).
-
The parameters are in a child component, and only the overall execution
results presented by its parent component need to be saved.
-
The parameters are in a calculation (i.e., Calculator component) or
a fast component (e.g., an application component with a fast runtime),
so that when the job is rerun, their values can be recalculated without
great cost, so that database look up is not required.
When a job is rerun (using the Rerun button on
the Runtime Gateway),
Isight
will, if possible, set the values of a component’s parameters for any
given run by looking up the values in a matching run of the original
job. If this is not possible, the component will be rerun. This lookup
is not possible if the component’s parameters were not saved.
Parameters not saved to the database affect database lookup in the
following ways:
-
Unsaved input parameters always prevent lookup. A component’s input/output
relation is usually not unique unless all inputs are satisfied.
-
Unsaved output parameters prevent lookup only if those parameters are
mapped to parameters in other components. Otherwise, the missing values
have no effect.
-
Unsaved local parameters never prevent lookup.