Introduction to Real-Time Systems - Google Groups

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Periodic Task Scheduling. 110 / 233. Page 2. Problem formulation. 111 / 233. Page 3. Timeline scheduling. 112 / 233 ...
Periodic Task Scheduling

110 / 233

Problem formulation

111 / 233

Timeline scheduling

112 / 233

Example

113 / 233

Implementation

114 / 233

Timeline scheduling

115 / 233

Timeline scheduling

116 / 233

Problems during overheads

117 / 233

Priority Scheduling

118 / 233

Rate Monotonic (RM)

119 / 233

How can we verify feasibility?

120 / 233

A necessary condition

121 / 233

An unfeasible RM schedule

122 / 233

Utilization upper bound

123 / 233

A different upper bound

124 / 233

The least upper bound

125 / 233

A sufficient condition

126 / 233

Ulub for RM

127 / 233

RM Guarantee test

128 / 233

Basic assumptions

129 / 233

RM Optimality

130 / 233

Critical instant

131 / 233

Computing Ulub

132 / 233

Computing Ulub for 2 tasks

133 / 233

Computing Ulub for 2 tasks

134 / 233

Computing Ulub for 2 tasks

135 / 233

Worst case for 2 tasks

136 / 233

Worst case for n tasks

137 / 233

Computing Ulub for n tasks

138 / 233

Computing Ulub for n tasks

139 / 233

The Hyperbolic bound

140 / 233

Proof sketch

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Proof sketch

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HB vs. LL

143 / 233

Earliest Deadline First (EDF)

144 / 233

EDF Example

145 / 233

The RM unfeasible schedule

146 / 233

EDF Optimality

147 / 233

EDF Optimality [Dertouzos! 74]

148 / 233

EDF schedulability

149 / 233

Extension to tasks with D < T

150 / 233

Deadline Monotonic (DM)

151 / 233

Response Time Analysis (RTA)

152 / 233

Computing Interference

153 / 233

Computing Response Time

154 / 233

Dynamic priority

155 / 233

Processor demand

156 / 233

Processor demand

157 / 233

Processor Demand Test

158 / 233

Bounding complexity

159 / 233

Bounding complexity

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Limiting L

161 / 233

Processor Demand Test

162 / 233

Summary

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Complexity issues

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RM vs. EDF

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Context switches

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RM vs. EDF: summary

167 / 233