L4-LINUX BASED SYSTEM AS A PLATFORM FOR EPICS IOC-CORE

The EPICS Input/Output Controller (IOC) coreprogram, iocCore [1], is now portable to multiplatforms. The Linux operating system, among them, seems to be a promising candidate for a platform to run iocCore, considering the recent high appreciation in desktop and server use as well as control fields. The Linux kernel, however, is not suitable for timecritical applications, since it responds to external events with unpredictable latency. We summarize three known causes of the latency, and then discuss some of the different solutions and how they affect the functionality of iocCore. As a possible alternative, we propose an approach that dispatches user-level processes by a real-time kernel aiming at a consistency of availability with predictable responsiveness.