Type-Safe Heterogeneous Sharing can be Fast

Safe sharing is a desirable feature of an object oriented database because it protects valuable database objects from program errors in application code. It is especially desirable in a heterogeneous environment in which applications are written in various programming languages, many of which have unsafe features. However, safe sharing is not without its potential performance costs. This paper explores these costs. It describes a number of techniques that improve performance without sacri cing safety, and presents results of experiments that evaluate their e ectiveness. The results show that some of these techniques are very promising, allowing safe sharing to be achieved with essentially no performance penalty.