Energy Consumption Reduction Techniques in Real-Time Embedded Systems

Öz

Real-time embedded systems are incorporated in every detail of our contemporary life from simple gadgets to avionics complex systems. Power is one of the important criteria for optimization in the design and operation of real-time embedded systems. Mainly used techniques to reduce energy consumption in the processor unit are dynamic voltage/ frequency scaling (DVFS), based on processor slowdown capabilities, and dynamic power management (DPM). In this study, using resource access protocols and real-time scheduling algorithms; MaxSpeed (MS) and critical section maximum speed (CSMS) techniques of DVFS and DPM were examined with examples run on the MCRTsim simulation program to obtain and compare results. The obtained results showed that applying such techniques can reduce energy consumption to ratios of 27% for the utilized examples.

Anahtar Kelimeler

• Real-time system
• Energy consumption
• DVFS
• DPM
• MCRTsim

Gerçek Zamanlı Gömülü Sistemlerde Enerji Tüketiminin Azaltılması için Teknikler

Öz

Gerçek zamanlı gömülü sistemler, basit gadget'lardan karmaşık aviyonik sistemlere kadar modern hayatımızın her detayına dahil edilmiştir. Güç, gerçek zamanlı gömülü sistemlerin tasarımı ve işletiminde optimizasyon için önemli ölçütlerden biridir. İşlemci biriminde enerji tüketimini azaltmak için başlıca kullanılan teknikler; işlemcinin yavaşlama faktörlerine dayalı dinamik voltaj/frekans ölçeklendirmesi (DVFS) ve dinamik güç yönetimi (DPM)dir. Bu çalışmada kaynaklara erişim protokolleri ve gerçek zamanlı zamanlama algoritmaları kullanarak; DVFS içerisinde yer alan MaxSpeed (MS) ve kritik bölüm maksimum hız (CSMS) teknikleri, ve DPM incelenmiş ve yapılan örnekler MCRTsim programı üzerinde çalıştırılıp sonuçları alınıp karşılaştırılmıştır. Elde edilen sonuçlar, bu tekniklerin uygulanmasının, kullanılan örneklerde enerji tüketimini %27'ye kadar azaltabileceğini göstermiştir.

Anahtar Kelimeler

• Gerçek zamanlı sistem
• Enerji tüketimi
• DVFS
• DPM
• MCRTsim

Kaynakça

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