{"title":"Modeling execution time of multi-stage N-version fault-tolerant software","authors":"M. Vouk, A. Paradkar, D. McAllister","doi":"10.1109/CMPSAC.1990.139422","DOIUrl":null,"url":null,"abstract":"The timing performance of N-version multi-stage software is analyzed for a strategy called expedient voting. In expedient voting the voting takes place as soon as an adequate number of components have finished the stage. The concept of a 'runahead' is introduced: the faster versions are allowed to run ahead of the rest of the slower versions by one or more stages, with synchronized re-start in the event of a failure. If the versions are highly reliable, inter-version failure dependence is small, and the difference between the fastest and the slowest successful components in each stage is large, then the execution speed-up through expedient voting may be substantial. Runaheads exceeding three stages offer diminishing returns. Speed-up deteriorates with reduction in the version reliability and independence.<<ETX>>","PeriodicalId":127509,"journal":{"name":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","volume":"51 1","pages":"0"},"PeriodicalIF":0.0000,"publicationDate":"1990-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"14","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings., Fourteenth Annual International Computer Software and Applications Conference","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/CMPSAC.1990.139422","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 14
Abstract
The timing performance of N-version multi-stage software is analyzed for a strategy called expedient voting. In expedient voting the voting takes place as soon as an adequate number of components have finished the stage. The concept of a 'runahead' is introduced: the faster versions are allowed to run ahead of the rest of the slower versions by one or more stages, with synchronized re-start in the event of a failure. If the versions are highly reliable, inter-version failure dependence is small, and the difference between the fastest and the slowest successful components in each stage is large, then the execution speed-up through expedient voting may be substantial. Runaheads exceeding three stages offer diminishing returns. Speed-up deteriorates with reduction in the version reliability and independence.<>