Hierarchy of Software Complexity Application Programs Sequential - PDF document

Hierarchy of Software Complexity Application Programs Sequential Programming Embedded Programming Middleware Concurrent Programming Distributed Programming Real-Time Programming Security Programming Reliable (FT) Programming Quality of Service Tradeoffs: accuracy , real-time, security, reliability, device constraints 1 Autopilot Example 2 1

Software Modules Structure 3 Timing 4 2

Distributed Scheduling Problem Space Taxonomy ������������������������� System ���������������������� E2E-1 Remote Calls E2E-N Local Only (per request) System Static Dynamic Conditions All Hard Hard/Soft All Soft Constraints All Periodic Periodic/Sporadic All Sporadic Periodicity 5 Priority Driven Example Precedence Graph J 1 , 3 J 2 , 1 J 3 , 2 J 4 , 2 J 6 , 4 J 5 , 2 J 7 , 4 J 8 , 1 Subscript indicates priority Number next to job indicates exec time J 5 released at time 4, all others at time 0 Jobs to be scheduled on two processors: P1 and P2 6 3

Priority Driven Example J1 J4 J6 P1 J7 J2 J3 J7 J5 J8 P2 0 2 4 6 8 10 12 preemptive P1 J1 J4 J5 J6 J2 J3 J7 J8 P2 0 2 4 6 8 10 12 non-preemptive 7 EDF Non-optimality Example J1 J2 J3 0 2 4 6 8 10 12 Missed EDF Schedule deadline J1 J3 J2 0 2 4 6 8 10 12 14 Feasible Schedule 8 4

Distributed Scheduling Problem Space Taxonomy ������������������������� System ���������������������� Liu E2E-1 Remote Calls E2E-N Local Only Ch 9 (per request) System Liu Ch 4 Static Dynamic Conditions All Hard Hard/Soft All Soft Constraints All Periodic Periodic/Sporadic All Sporadic Periodicity Liu Ch 6 Liu Ch 7 9 Distributed Scheduling Solution Space Taxonomy Scheduling ������������ ���������������� �������������� Adaptive Fixed Adaptive? ���������������� ���������� ����� Analysis Offline Only On/Offline Online Only ������������ �����!������ Mechanism Priority Reservation ���������������� ����������� Parameters Dynamic Static � ���������� ���������� ��������� ���������� ��������� ������ Algorithms ���������� �������� 10 5