A customer with two types of jobs arrive at a Poisson arrival and exponential server queue. Job A is processed in one queueing sytem and job B can be processed if he is not in the queueing system. The process of job B consists of several tasks at the end of any task process. At each end of the task process, he makes a decision whether he should suspend the process of job B and join the queue to process job A. If he decides to join the queue, he resumes job B when job A is finished. The authors minimize the expected time until two jobs are completed using a dynamic programming formulation.