Reliability-aware data placement for partial memory protection in embedded processors

Low cost protection of embedded systems against soft errors has recently become a major concern. This issue is even more critical in memory elements that are inherently more prone to transient faults. In this paper, we propose a reliability aware data placement technique in order to partially protect embedded memory systems. We show that by adopting this method instead of traditional placement schemes with complete memory protection, an acceptable level of fault tolerance can be achieved while incurring less area and power overhead. In this approach, each variable in the program is placed in either protected or non-protected memory area according to the profile-driven liveness analysis of all memory variables. In order to measure the level of fault coverage, we inject faults into the memory during the course of program execution in a Monte Carlo simulation framework. Subsequently, we calculate the coverage of partial protection scheme based on the number of protected, failed and crashed runs during the fault injection experiment.