An apparatus and a job scheduling method are provided. For example, the apparatus is a multi-core processing apparatus. The apparatus and method minimize performance degradation of a core caused by sharing resources by dynamically managing a maximum number of jobs assigned to each core of the apparatus. The apparatus includes at least one core including an active cycle counting unit configured to store a number of active cycles and a stall cycle counting unit configured to store a number of stall cycles and a job scheduler configured to assign at least one job to each of the at least one core, based on the number of active cycles and the number of stall cycles. When the ratio of the number of stall cycles to a number of active cycles for a core is too great, the job scheduler assigns fewer jobs to that core to improve performance.