On the basis of a further research on software redundancy, two important performance indexes, data synchronization time and master-reserve change-over time are both analyzed, and some formulas are concluded. 在熟知软冗余工作原理的基础上,本文对软冗余的两个重要性能指标:主备切换时间和数据同步时间,进行了进一步的研究。