Chapter 7 Characteristics
The heuristics performed by the adequation use the characteristics of each operation and each data dependence relatively to the operators and media it may be distributed onto. Presently we are mainly interested in real-time performances. Therefore the operations of algorithm graphs must be characterized in terms of duration relatively to the operators and media of architecture graphs.
7.1 Execution durations
7.1.1 Operation durations
In the algorithm window,
right click on the background
of an algorithm definition window.
Choose the Durations option.
It opens a dialog window
in which you can set the execution durations of the operation
by operator
(e.g. u/U = 3
specifies the duration required to execute the target operation
on an u/U operator).
An operation duration has the following syntax:
operation_duration ::= operator_definition_name "=" value
where:
- operator_definition_name specifies an operator,
- value specifies the duration as an integer time unit.
7.1.2 Operator durations
In an operator definition window, left click on the
Modify durations button. It opens a dialog window in which
you can set the execution durations on the operator by operation
(e.g. bool/AND = 2 specifies the duration required to
execute a bool/AND operation on the target operator).
An operator duration has the following syntax:
operator_duration ::= operation_definition_name "=" value
where:
- operation_definition_name specifies an operation,
- value specifies the duration as an integer time unit.
7.2 Communication durations
In a medium definition window,
left click on the Modify durations button.
It opens a dialog window
in which you can set the communication durations
on the communication medium
by data type
(e.g. u/bool = 1
specifies the duration required
to transfer one element of type u/bool
on the target communication medium).
A medium duration has the following syntax:
medium_duration ::= data_type "=" value
where:
- data_type specifies a basic data type,
- value specifies the duration as an integer time unit.
7.3 Libraries
Figure 7.1: u/U durations window in examples/basic_with_library/basicBiProc/basicBiProc.sdx
In case of a duration already specified in a library,
a lib/operator_definition_name = value
or
lib/operation_definition_name = value
or lib/data_type = value line
will appear in the corresponding duration windows
(cf. figure 7.1).
You can modify durations of local and global definitions.
Modifications on a duration of a global definition
impact only the current application
and will not be saved with the current application.