EFFECTS OF CONTEXT VIOLATION ON EXECUTION RESULT IN LOCAL-LAG ALGORITHM

摘要

Local-lag algorithm is an efficient way to maintain consistency for replicated continuous applications which have a high requirement on accuracy. However, local-lag algorithm will lead to context violation, which may induce the execution result of an operation to be violated (I.e., result violation). In this paper, the definitions of context violation and result violation are presented and the relationship between these two violations is analyzed.Besides, a game named X-Spaceship, which adopts the local-lag algorithm, is employed to study the effects of context violation on the execution result in a particular system. The experiment results indicate that the probability of result violation happening increases fast with lag value when lag value ranges from 0 ms to 200 ms,when lag value exceeds 200 ms, it exceeds 0.7 in some situations.