Architecture Modeling - SPES 2020

Architecture Modeling
tasks Command1 and Monitor1 are not met. To get more detailed information about a deadline
violation one may choose a red skull and a window opens as it is depicted in Figure 5.23
for the task Command1. At the top of the window, we see beside the name, period and deadline
of the node a list of different results of the analysis. First of all, this is the response time and
how it is composed of different aspects as the blocking time by tasks with higher priority. This
is depicted at the bottom of Figure 5.23. The red line represents the deadline that is obviously
violated here.
One possible counter-measure to solve this violation would be two replace one or both ECUs
by other ones where the respective tasks have less execution times. In this example, the initial
architecture consists of two ECUs of an ARM7 type. When replacing both ECUs by an ARM9
type leading to less execution times, all deadline violations can be successfully removed. Another
possible measure would be to change the splitting of global deadlines into local deadlines
(deadline synthesis) in the SPES model.
5.2 On the role of contracts in system development
processes 5
In this section we discuss key design challenges
• Coping with complexity of systems
• Coping with the complexity of the supply chain
• Getting initial requirements right
• Coping with multi-layer design optimization
• Managing Risk
facing systems companies, and discuss industrial solutions in place to cope with these, and
point out how conservative extensions of current processes exploiting contract-based design
could tackle such weaknesses. We wrap up by condensing the essence of what we call contractbased
design.
5.2.1 Coping with complexity of systems
Multiple lines of attack have been developed by industry to cope with the exponential growth
in systems complexity:
1. Model-based development
2. Virtual integration
3. Layered design
4. Component-based design
5. Platform-based design
5 This section is co-authored with Alberto L. Sangiovanni-Vincentelli, University of California at Berkeley
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