Joins or chords is a concurrency construct that seems to fit well with the object oriented paradigm. Chorded languages are presented with implicit assumptions regarding the fair treatment of processes by the scheduler. We define weak and strong fairness for the Small Chorded Object-Oriented Language (
SCHOOL) which allows the classification of executions as fair. We investigate the liveness behaviour of programs and establish worst-case behaviours in terms of scheduling delays.
We discover that weak fairness, although giving the scheduler implementer greater freedom in selecting the next process which is to be executed, is harder to implement than strong fairness; strong fairness benefits from a straightforward implementation, however, imposes many more constraints and limits the selection function of a scheduler.