{"title":"Real time recovery of fault tolerant processing elements","authors":"T. Sims","doi":"10.1109/DASC.1996.559204","DOIUrl":null,"url":null,"abstract":"A critical problem in the design of ultra-reliable fault tolerant systems is that of how to bring a redundant member back on-line, after a transient fault, without degrading critical real-time functions. Recovery from transients is imperative to maintain necessary system reliability in the face of transient errors which have been estimated to occur at a rate of 5 to 100 times that of permanent failures. Excessive delays associated with recovery become a problem when as much as 1 Mbytes of RAM in the faulty processor must be made congruent with the processing majority while maintaining full functionality of critical, real-time control algorithms. This paper describes a hardware assisted recovery technique which uses memory \"tags\" to determine which memory segments need to be restored such that recovery can be performed incrementally without affecting real-time operational tasks. Also presented is performance data associated with this technique's application to a Draper Laboratory quad-redundant processor responsible for vehicle control of a manned undersea vehicle.","PeriodicalId":332554,"journal":{"name":"15th DASC. AIAA/IEEE Digital Avionics Systems Conference","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1996-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"9","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"15th DASC. AIAA/IEEE Digital Avionics Systems Conference","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/DASC.1996.559204","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 9
Abstract
A critical problem in the design of ultra-reliable fault tolerant systems is that of how to bring a redundant member back on-line, after a transient fault, without degrading critical real-time functions. Recovery from transients is imperative to maintain necessary system reliability in the face of transient errors which have been estimated to occur at a rate of 5 to 100 times that of permanent failures. Excessive delays associated with recovery become a problem when as much as 1 Mbytes of RAM in the faulty processor must be made congruent with the processing majority while maintaining full functionality of critical, real-time control algorithms. This paper describes a hardware assisted recovery technique which uses memory "tags" to determine which memory segments need to be restored such that recovery can be performed incrementally without affecting real-time operational tasks. Also presented is performance data associated with this technique's application to a Draper Laboratory quad-redundant processor responsible for vehicle control of a manned undersea vehicle.