Avionic software is the subject of stringent real time, determinism and safety constraints. Software designers face several challenges, one of them being the interferences that appear in common situations, such as resource sharing. The interferences introduce non-determinism and delays in execution time. One of the main interference prone resources are cache memories. In single-core processors, caches comprise multiple private levels. This breaks the isolation principle imposed by avionic standards, such as the ARINC-653. This standard defines partitioned architectures where one partition should never directly interfere with another one. In cache-based architectures, one partition can modify the cache content of another partition. In this paper, we propose a method based on cache locking to reduce the non-determinism and the contention on lower level memories while improving the time performances.

Avionic software is the subject of critical real time, determinism and safety constraints. Software designers face several challenges, one of them being the estimation of worst-case execution time (WCET) of applications, that dictates the execution time of the system. A pessimistic WCET estimation can lead to low execution performances of the system, while an over-optimistic estimation can lead to deadline misses, breaking one the basic constraints of critical real-time systems (RTS). Partitioned systems are one special category of real time systems, employed by the avionic community to deploy avionic software. The ARINC-653 standard is one common avionic standard that employs the concept of partitions. This standard defines partitioned architectures where one partition should never directly interfere with another one. Assessing WCET of general purpose RTSs is achievable by the usage of one of the many published benchmark or WCET estimation frameworks. Contrarily, partitioned RTSs are special cases, in which common benchmark tools may not capture all the metrics. In this document, we present SFPBench, a generic benchmark framework for the assessment of performance metrics on partitioned RTSs. The general organization of the framework and its applications are illustrated, as well as an use-case, employing SFPBench on an industrial partitioned operating system (OS) executing on a Commercial Off-The-shelf (COTS) processor.Operating Systems (OSs) provide an interface between the software applications and their host hardware systems. One of their main roles is to manage the system's resources to make their usage transparent to the user. This enables applications to run on hardware systems without being aware of these systems' specifications, easing the development of applications. Real-Time Operating Systems (RTOS) are operating systems designed for real-time management. RTOSs are used for critical systems for which a given functionality must be done within a given time interval. An RTOS must ensure that the worst-case execution time (WCET) of each task is respected. The ARINC-653 [1] is an avionic standard which defines a general-purpose APplication/EXecutive (APEX) interface (API) between the Core

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