Java RMI

Important Questions WhenThinking About Servers

In Chapter 5, we introduced two major problems that arise in the design of distributed applications: network latency and the possibility of partial failure. Clearly, when designing a server (or choosing between design alternatives), you should take these problems into account. In particular, your goal should be to minimize the impact of network latency and to avoid the problems caused by partial failures.

The problem is translating the desire to avoid these problems into specific design criteria. What follows is a list of questions you should ask yourself when making design decisions or evaluating designs. This list isn’t intended to be complete; as you get more experienced at designing distributed systems, you will undoubtedly come up with more questions, and your own ways of thinking about these problems. It is, however, a good start.

Client-Side Caching

There is an ugly truth lurking in the attempts to minimize problems caused by either network latency or the possibility of partial failures. Often, the attempt to mitigate these problems will cause other, equally vexing, problems to arise. Consider, for example, the problem of network latency. One solution to this problem is to implement a client-side cache.

The idea is simple: in a data-intensive application (say, for example, an application that allows users to view information from a database), the client should fetch only a given piece of data once. Though this seems reasonable, ...