Abstract: We investigate the problem of the online scheduling with kind release times and job compatibilities on a single unbounded parallel-batch machine to minimize makespan. The kind release times (KRT) means that under the online setting no jobs can be released when the machine is busy. What associated with each job \begin{document}$ J_{j} $\end{document} are its normal processing time \begin{document}$ p_j $\end{document} and release time \begin{document}$ r_j $\end{document}. Two jobs \begin{document}$ J_i $\end{document} and \begin{document}$ J_j $\end{document} are called compatible if \begin{document}$ \max \{p_i, p_j\} \leqslant (1+a) \min \{p_i, p_j\} $\end{document}, where a is a given positive constant. Compatible jobs could be processed in the same batch. We derive a best possible online algorithm with a competitive ratio of \begin{document}$ 1+\sqrt{\lambda ^{2}-\lambda +1}-\lambda $\end{document}, where \begin{document}$ \lambda =\frac{a}{1+a} $\end{document}.

Key words: Online scheduling, Kind release time, Compatibility, Batch machine, Competitive ratio