Jobs submitted into a cluster have varying requirements depending on user-specific needs and expectations. Therefore, in utility-driven cluster computing, cluster Resource Management Systems (RMSs) need to be aware of these requirements in order to allocate resources effectively. Service Level Agreements (SLAs) can be used to differentiate different value of jobs as they define service conditions that the cluster RMS agrees to provide for each different job. The SLA acts as a contract between a user and the cluster whereby the user is entitled to compensation whenever the cluster RMS fails to deliver the required service. In this paper, we present a proportional share allocation technique called LibraSLA that takes into account the utility of accepting new jobs into the cluster based on their SLA. We study how LibraSLA performs with respect to several SLA requirements that include: (i) deadline type whether the job can be delayed, (ii) deadline when the job needs to be finished, (i...