A Run-time Partitioning Algorithm for RTOS on Reconfigurable Hardware ⋆ MarceloG¨otz 1 , Achim Rettberg 2 , and Carlos Eduardo Pereira 3 1 Heinz Nixdorf Institute University of Paderborn, Germany mgoetz@uni-paderborn.de 2 C-LAB University of Paderborn, Germany achim@c-lab.de 3 Departamento de Engenharia Eletrica UFRGS - Universidade Federal do Rio Grande do Sul - Brazil cpereira@eletro.ufrgs.br Abstract. In today’s system design, reconfigurable computing plays more and more an important role. By the extension of reconfigurable devices like FPGAs with one or more CPUs new challenges in system de- sign should be solved. These new hybrid FPGAs (e.g. Virtex-II Pro TM ), provides a hardcore general-purpose processor (GPP) embedded into a field of programmable gate arrays. Furthermore, they offer partial recon- figuration. Therefore, those hybrid FPGAs are very attractive for imple- mentation of run-time reconfigurable embedded systems. However, most of the efforts in this field were made in order to apply these capabilities at application level, leaving to the Operating System (OS) the provision of the necessary mechanisms to support these applications. In this paper, an approach for run-time reconfigurable Operating System, which takes advantage of the new hybrid FPGAs to reconfigure itself based on online estimation of application demands, is presented. Especially run-time as- signment and reconfiguration of OS services over hybrid architecture are discussed. The proposed model uses a 0-1 Integer programming strategy for assigning OS components over hybrid architecture, as well as an al- ternative heuristic algorithm for it. Furthermore, the evaluation of the reconfiguration costs are presented and discussed. 1 INTRODUCTION Nowadays, the usage of Field Programmable Gate Array (FPGA) in the field of Reconfigurable Computing (RC) has become widely used. In particular the capability of a FPGA to be run-time reprogrammed makes its use for recon- figurable systems very attractive Even more attractive is the emerging hybrid ⋆ This work was developed in the course of the Special Research Initiative 614 - Self- optimizing Concepts and Structures in Mechanical Engineering - University of Pader- born, and was published on its behalf and funded by the Deutsche Forschungsge- meinschaft.