Int. J. Critical Computer-Based Systems, Vol. 4, No. 3, 227{247 1 Efficient Online Memory Error Assessment and Circumvention for Linux with RAMpage Horst Schirmeier*, Ingo Korb, Olaf Spinczyk and Michael Engel Department of Computer Science 12, Technische Universit¨atDortmund, Otto-Hahn-Str. 16, 44221 Dortmund, Germany E-mail:
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[email protected] *Corresponding author Abstract: Memory errors are a major source of reliability problems in computer systems. Undetected errors may result in program termination or, even worse, silent data corruption. Recent studies have shown that the frequency of permanent memory errors is an order of magnitude higher than previously assumed and regularly affects everyday operation. To reduce the impact of memory errors, we designed RAMpage, a purely software-based infrastructure to assess and circumvent permanent memory errors in a running commodity x86-64 Linux-based system. We briefly describe the design and implementation of RAMpage and present new results from an extensive qualitative and quantitative evaluation. These results show the efficiency of our approach { RAMpage is able to provide a smooth graceful degradation in the presence of permanent memory errors while requiring only a small overhead in terms of CPU time, energy, and memory space. Keywords: Memory errors; Software-based fault tolerance; DRAM chips; Silent data corruption; Operating systems; Reliable operation Biographical notes: Horst Schirmeier received his Diploma in Computer Science from Friedrich-Alexander-Universit¨atErlangen, Germany. He worked as a researcher in the System Software group at FAU Erlangen, and is currently working in the field of resilient infrastructure software and fault resilience assessment for the DanceOS project in the Embedded System Software group at Technische Universit¨atDortmund, Germany.