Non Pre-Emptive Scheduling of Messages on SMTV Token-Passing Networks
Ref: HURRAY-TR-9924 Publication Date: 19, Jun, 2000
Non Pre-Emptive Scheduling of Messages on SMTV Token-Passing NetworksRef: HURRAY-TR-9924 Publication Date: 19, Jun, 2000
Fieldbus communication networks aim to interconnect sensors, actuators and controllers within distributed computer-controlled systems. Therefore, they constitute the foundation upon which real-time applications are to be implemented. A specific class of fieldbus communication networks is based on a simplified version of token-passing protocols, where each station may transfer, at most, one Single Message per Token Visit (SMTV). In this paper, we establish an analogy between non pre-emptive task scheduling in single processors and scheduling of messages on SMTV token-passing networks. Moreover, we clearly show that concepts such as blocking and interference in non pre-emptive task scheduling have their counterparts in the scheduling of messages on SMTV token-passing networks. Based on this task/message scheduling analogy, we provide pre-run-time schedulability conditions for supporting real-time messages with SMTV token-passing networks. We provide both utilisation-based and response time tests to perform the pre-run-time schedulability analysis of real-time messages on SMTV token-passing networks, considering RM/DM and EDF priority assignment schemes.
12th IEEE Euromicro Conference on Real-Time Systems, Edited: IEEE Computer Society, pp 209-218.