The Embedded Processor Market, evolving since the introduction of the first microprocessor from Intel, responds to growing demands for enhanced computational power by extensive use of multicore processors. Real-time embedded systems in various sectors like space, defense, avionics, and telecommunication require faster, more efficient processors. Single-core processors with increased clock frequency have reached saturation and this led to the rise of multicore processors. This evolution poses great challenges for the software designers to develop applications for multi-core processors that meet the stringent timing requirements of the real-time systems. In multi-core processors ported with Linux, the scheduler depending on the scheduling policy selected, the OS related tasks and the application tasks are assigned to any of the core. The application developer does not have much control over this. The multiple cores on the SoC share the LLC and this has a major impact on the execution time of the tasks. Scheduling of the Linux tasks along with application tasks on any core of the multicore processor seriously affects the schedulability of the real-time tasks and leads to deadline misses. This paper examines the effect of CPU isolation on real-time embedded systems realized using multicore processors ported with Linux to address this issue.