Transparent and Selective Real-Time Interrupt Services for Performance Improvement

Abstract

The popularity of mobile and multimedia applications made real-time support a mandatory feature for embedded operating systems. However, the current situation is that the overall performance is significantly degraded due to the real-time support. This paper suggests a novel scheme to minimize the performance degradation in embedded operating systems with real-time support. Especially, we propose transparent and selective real-time interrupt services which transparently monitor the system and postpone interrupt handling that are not relevant to real-time tasks. The proposed scheme was implemented on the Linux 2.6 kernel and the experimental results show that our scheme improves the throughput by up to 86% for Hackbench benchmark while providing almost the same scheduling latency compared to the previous work.

The Real-Time Linux Kernel

“…However, the metrics selected in this paper are not representative of the throughput degradation, since most of the metrics are related to system latencies. Already in the first years of the PRE-EMPT_RT patch, Jeong et al (2007) noticed that the actual throughput may be reduced by a factor of 5, but bounding the frequency of context switches may help to maintain an acceptable performance level. Later, the same authors analyzed the throughput degradation in Seo et al (2009) experiencing a worst-case degradation of 10 times.…”