Title
To preempt or not to preempt, that is the question
Abstract
Real-time operating systems (RTOSes) are traditionally designed to be fully preemptible. This improves the average interrupt response time of the system but increases kernel complexity. An alternative design is to make the kernel mostly non-preemptible and only handle pending interrupts at specific pre-emption points within the kernel. While this potentially worsens interrupt response times, we claim that for a protected-mode RTOS, as required for multi-criticality systems, non-preemptible kernels can achieve worst-case latencies comparable to those of fully-preemptible kernels. In order to understand the latency limits achievable in both approaches, we analyse and compare the worst-case interrupt latencies of a fully-preemptible commercial RTOS (QNX Neutrino) and a non-preemptible real-time kernel (seL4). Our results indicate that a non-preemptible kernel can achieve interrupt latencies which are within a factor of two from those exhibited by a fully-preemptible kernel.
Year
DOI
Venue
2012
10.1145/2349896.2349904
ApSys
Keywords
DocType
Citations 
worst-case interrupt latency,increases kernel complexity,worsens interrupt response time,interrupt latency,non-preemptible kernel,fully-preemptible commercial rtos,fully-preemptible kernel,protected-mode rtos,average interrupt response time,non-preemptible real-time kernel,fault tolerance,real time,real time operating system
Conference
3
PageRank 
References 
Authors
0.40
6
3
Name
Order
Citations
PageRank
Bernard Blackham1694.41
Vernon Tang230.40
Gernot Heiser32525137.42