Avaliação do determinismo temporal no tratamento de interrupções em plataformas de tempo real Linux
Resumo
Várias extensões Linux para tempo real podem ser encontradas hoje em dia. Duas delas têm recebido atenção especial recentemente: os patches Preempt-RT e Xenomai. Este artigo avalia em que medida elas fornecem garantias determinísticas quando reagem a eventos externos, uma característica essencial quando se trata de sistemas de tempo real. Para tanto, definimos uma abordagem experimental simples e eficaz. Os resultados obtidos indicam que Preempt-RT é mais propenso a variações temporais que Xenomai quando o sistema está sujeito a cenários de sobrecarga.Referências
Abeni, L., Goel, A., Krasic, C., Snow, J., and Walpole, J. (2002). A measurement-based analysis of the real-time performance of the linux kernel. In Proc. of the Real-Time Technology and Applications Symposium (RTAS02), pages 1–4.
Benoit, K. and Yaghmour, K. (2005). Preempt-RT and I-pipe: the numbers. [link]. Last access 03/08.
Calandrino, J., Leontyev, H., Block, A., Devi, U., and Anderson, J. (2006). LitmusRT : A testbed for empirically comparing real-time multiprocessor schedulers. In In Proceedings of the 27th IEEE Real-Time Systems Symposium, pages 111–126.
D. P. Bovet, M. C. (2005). Understanding the Linux Kernel. O’Reilly, 3rd edition.
Dozio, L. and Mantegazza, P. (2003). Linux real time application interface (RTAI) in low cost high performance motion control. In Proceedings of the conference of ANIPLA, Associazione Nazionale Italiana per l’Automazione.
Fry, G. and West, R. (2007). On the integration of real-time asynchronous event handling mechanisms with existing operating system services. In Proceedings of the International Conference on Embedded Systems and Applications (ESA’07).
I. Molnar et al. (2008). PreemptRT. [link] - Last access jan. 08.
L. Torvalds et al. (2008). Kernel. [link] - Last access jan. 08.
Liu, J. W. S. (2000). Real-Time Systems. Prentice-Hall.
Marchesotti, M., Migliardi, M., and Podestà, R. (2006). A measurement-based analysis of the responsiveness of the Linux kernel. In Proc. of the 13th Int. Symposium and Workshop on Engineering of Computer Based Systems, volume 0, pages 397–408. IEEE Computer Society.
McKenney, P. (2005). A realtime preemption overview. [link] - Last access dez. 07.
McVoy, L. W. and Staelin, C. (1996). lmbench: Portable tools for performance analysis. In USENIX Annual Technical Conference, pages 279–294.
P. Gerum et al. (2008). Xenomai. [link] - Last access jan. 08.
P. Mantegazza et al. (2008). RTAI. [link] - Last access jan. 08.
Pratt, S. L. and Heger, D. A. (2004). Workload dependent performance evaluation of the linux 2.6 i/o schedulers. In Proceedings of the Linux Symposium, pages 425–448.
Regnier, P. (2008). Especificação formal, verificação e implementação de um protocolo de comunicação determinista, baseado em ethernet. Master’s thesis, Universidade Federal da Bahia.
Rostedt, S. and Hart, D. V. (2007). Internals of the rt patch. In Proceedings of the Linux Symposium, pages 161–172.
Sha, L., Rajkumar, R., and Lehoczky, J. P. (1990). Priority Inheritance Protocols: An approach to real-time synchronisation. IEEE Transaction on Computers, 39(9):1175–1185.
Siro, A., Emde, C., and McGuire, N. (2007). Assessment of the realtime preemption patches (RT-Preempt) and their impact on the general purpose performance of the system. In Proceedings of the 9th Real-Time Linux Workshop.
Stodolsky, D., Chen, J., and Bershad, B. (1993). Fast interrupt priority management in operating systems. In Proc. of the USENIX Symposium on Microkernels and Other Kernel Architectures, pages 105–110.
V. Yodaiken et al. (2008). RT-Linux. [link] - Last access jan. 08.
Yaghmour, K. (2001). The real-time application interface. In Proceedings of the Linux Symposium.
Benoit, K. and Yaghmour, K. (2005). Preempt-RT and I-pipe: the numbers. [link]. Last access 03/08.
Calandrino, J., Leontyev, H., Block, A., Devi, U., and Anderson, J. (2006). LitmusRT : A testbed for empirically comparing real-time multiprocessor schedulers. In In Proceedings of the 27th IEEE Real-Time Systems Symposium, pages 111–126.
D. P. Bovet, M. C. (2005). Understanding the Linux Kernel. O’Reilly, 3rd edition.
Dozio, L. and Mantegazza, P. (2003). Linux real time application interface (RTAI) in low cost high performance motion control. In Proceedings of the conference of ANIPLA, Associazione Nazionale Italiana per l’Automazione.
Fry, G. and West, R. (2007). On the integration of real-time asynchronous event handling mechanisms with existing operating system services. In Proceedings of the International Conference on Embedded Systems and Applications (ESA’07).
I. Molnar et al. (2008). PreemptRT. [link] - Last access jan. 08.
L. Torvalds et al. (2008). Kernel. [link] - Last access jan. 08.
Liu, J. W. S. (2000). Real-Time Systems. Prentice-Hall.
Marchesotti, M., Migliardi, M., and Podestà, R. (2006). A measurement-based analysis of the responsiveness of the Linux kernel. In Proc. of the 13th Int. Symposium and Workshop on Engineering of Computer Based Systems, volume 0, pages 397–408. IEEE Computer Society.
McKenney, P. (2005). A realtime preemption overview. [link] - Last access dez. 07.
McVoy, L. W. and Staelin, C. (1996). lmbench: Portable tools for performance analysis. In USENIX Annual Technical Conference, pages 279–294.
P. Gerum et al. (2008). Xenomai. [link] - Last access jan. 08.
P. Mantegazza et al. (2008). RTAI. [link] - Last access jan. 08.
Pratt, S. L. and Heger, D. A. (2004). Workload dependent performance evaluation of the linux 2.6 i/o schedulers. In Proceedings of the Linux Symposium, pages 425–448.
Regnier, P. (2008). Especificação formal, verificação e implementação de um protocolo de comunicação determinista, baseado em ethernet. Master’s thesis, Universidade Federal da Bahia.
Rostedt, S. and Hart, D. V. (2007). Internals of the rt patch. In Proceedings of the Linux Symposium, pages 161–172.
Sha, L., Rajkumar, R., and Lehoczky, J. P. (1990). Priority Inheritance Protocols: An approach to real-time synchronisation. IEEE Transaction on Computers, 39(9):1175–1185.
Siro, A., Emde, C., and McGuire, N. (2007). Assessment of the realtime preemption patches (RT-Preempt) and their impact on the general purpose performance of the system. In Proceedings of the 9th Real-Time Linux Workshop.
Stodolsky, D., Chen, J., and Bershad, B. (1993). Fast interrupt priority management in operating systems. In Proc. of the USENIX Symposium on Microkernels and Other Kernel Architectures, pages 105–110.
V. Yodaiken et al. (2008). RT-Linux. [link] - Last access jan. 08.
Yaghmour, K. (2001). The real-time application interface. In Proceedings of the Linux Symposium.
Publicado
12/07/2008
Como Citar
REGNIER, Paul; LIMA, George; BARRETO, Luciano.
Avaliação do determinismo temporal no tratamento de interrupções em plataformas de tempo real Linux. In: WORKSHOP DE SISTEMAS OPERACIONAIS (WSO), 5. , 2008, Belém/PA.
Anais [...].
Porto Alegre: Sociedade Brasileira de Computação,
2008
.
p. 13-24.
