Aimed at the scheduling problem of dynamic segment of FlexRay

the formulas both for message transmission period and the length of message frame are put forward firstly which are unrelated to FID assignment based on the AUTOSAR specification

and then a BIP model is built based on the load balancing of parallel multi-processor scheduling model.To solve the large scale message scheduling problem

a period increasing longest-processing-time-first (PILPT) algorithm is proposed as well as a phase reserving LPT (PRLPT) algorithm

which is proposed to prevent the longer period message from occupying the position of the shorter

and a general suggestion for the choice between the two algorithms is given finally.The simulation results show that

whether for the fixed message set of J1939 or variable message set with a large number of messages and wide length distribution

PILPT and PRLPT algorithms both have outstanding performance in optimizing ratio

load balance and the calculating speed.