def getServiceJobsToStart(self, maxWait):
        """
        :param float maxWait: Time in seconds to wait to get a job before returning.
        :return: a tuple of (serviceJobStoreID, memory, cores, disk, ..) representing
        a service job to start.
        :rtype: toil.job.ServiceJobNode
        """
        try:
            serviceJob = self._serviceJobGraphsToStart.get(timeout=maxWait)
            assert self.jobsIssuedToServiceManager >= 0
            self.jobsIssuedToServiceManager -= 1
            return serviceJob
        except Empty:
            return None